grounded design: landscape + culture

Perennials to Interplant in Grasses

noreply@blogger.com (Thomas) — Fri, 13 Jan 2012 03:54:00 +0000

Of all my plant obsessions, herbaceous plants are among my favorites. Several years back, I remember walking through the woods with a colleague, a tree expert. After several hundred yards, we laughed at each other. He was always looking up at the canopies, and I was always looking down at the ground—scanning the forest floor for herbaceous plants. It is my perpetual posture: head down, scanning right to left.

Amphora canescens

As a perpetual ground-scanner, I’ve recently had a revelation about the way many perennials and grasses are meant to grow together. This revelation has influenced the way I design.

It’s actually quite simple: many perennials from meadow/prairie ecosystems have evolved to grow within a matrix of grasses. While that is not a particularly ground-breaking concept, it does challenge the way many perennial gardeners arrange their plants. Most perennial gardens focus heavily on forbs (blooming perennials) that are scattered one by one in planting beds. Grasses, if used at all, tend to be added as specimens or accents. But if you consider the way most meadow perennials grow, this ratio should be reversed. The grasses are meant to be the dominant plants with forbs emerging through this matrix.

Consider the morphology of an Echinacea (Cone Flower). Echinaceas typically have low basal foliage and tall spindly stems which support the flowers. This very structure is designed to help the plant grow out of a lot of grasses. The low foliage first emerges in late spring before the warm season grasses emerge, grabbing sunlight to ready the plant for its flowering. Once the grasses put on their height, the Cone Flower sends up its flowers on delicate stalks. The grasses support the flower (like a stake). If you’ve ever had perennials flop over, it may be because it is missing its support system.

As a gardener or designer, this does not mean that your perennial gardens need to be mostly grasses. It does, however, provide a real opportunity for people interested in designing with ornamental grasses. I love the look of large masses of ornamental grasses in a landscape. They are easy, low maintenance, have a long season of interest (particularly in winter), and add a wonderful looseness and spontaneity to a landscape.

Dalea purpurea growing in grasses

Any time you plant a mass of ornamental grasses, you can interplant them with perennials. It just so happens to be an excellent strategy for low maintenance gardening. The grasses cover the ground and provide a long-season of reliable interest; and the perennials emerge through the grasses as a colorful accent. I typically use a ratio of 90:10 or 80:20 grasses to perennials. That allows the grasses to still read as a continuous mass, providing legibility and tranquility to the composition.

This strategy is particularly good for people who are worried that grasses look too wild or weedy in a landscape setting. The presence of blooming perennials makes the grasses helps the composition look more gardenesque, less wild.

Aesclepias tuberosa and Veronicastrum virginicum

So how do you interplant perennials in grasses? Be sure to carefully select the right perennials to plant with the right grasses. Any time you interplant two different species, the species compete with each other. Sometimes the grasses (who tend to have superior root systems) will “eat” the perennial accents after a few years. The key is to pair perennials and grasses of the same basic height and competitiveness. If the perennial towers over the grass, the composition can look too chaotic. Use perennials that are equal or just slightly taller than the grass it is planted in. It is also important to pay attention to the origin of the perennial. Use perennials that have evolved from a meadow setting as opposed to a woodland floor setting. They have very different competitive strategies.

Echinacea, Liatris, and Aesclepias interplanted in a mass of Sporobolus heterolepsis

Through lots of trial and error, I have found that perennials with vertical habits (as opposed to spreading or mounding habits) look the best in a sea of grasses. Mounding perennials can create larger “holes” within a mass of grasses, weakening the visual legibility of the massing.

Below, I have created a chart of perennials that are especially good to interplant within a mass of ornamental grasses. How you arrange your perennial accents depends on the scale of the grasses their planted in. In really large grass area, it’s possible to create drifts and hints of patterns with the perennials. In smaller massings, you may want to dot perennials individually or in small clusters of 3 or 5.

Interplanting is one of the more challenging aspects of gardening. To be honest, the majority of my experiments in mixing perennials have resulted in messy, chaotic compositions. But the handful of successes is worth the effort. Have you successfully interplanted perennials in grasses? What worked for you?

Garden Design Trends 2012

noreply@blogger.com (Thomas) — Thu, 05 Jan 2012 22:11:00 +0000

Cleve West's winning design for Chelsea Flower Show

Each New Year, the internet is abuzz with it the inevitable horde of prophets and trend-watchers, confidently predicting the themes of the year. Of course, there is absolutely no accountability for these supposed experts because once the buzz of the New Year fades, the predictions are forgotten. I may be one of the few people on the planet who actually loves New Year prognostications. Finding meta-themes from the sea of quotidian activities appeals to my philosophic bent; for me, it is a puzzle game: I love the thrill of finding a pattern among scattered pieces.

So it is with great delight that I present to you my attempt at New Year trend-spotting. This year, my trends focus on trends in garden design (it’s best to stick to what I know, right?). For the last few weeks, I have spent time contemplating great gardens designed in the last year. What was it about these spaces that captured the zeitgeist? What about them moved me? What aspects of them will likely be replicated?

1. The New Romanticism: Garden design in 2012 will mark a return to romanticism. For the last decade, the focus on sustainable gardens has brought a decidedly rationalistic overlay to garden design. After all, the focus on sustainable techniques such as stormwater, native species, and xeriscaping has emphasized scientific and ecological processes. In addition, modernism has been a big theme in garden design over the last decade, bringing with it a focus on functionalistic design. While I expect sustainable and modernistic designs to continue, new gardens will be less cerebral and more emotional and spiritual bent. Expect to see a revival of all sorts of old, classical garden styles such as cottage gardening, French and Italian formal gardens, and even medieval gardens updated with a modern twist. Romanticism is all about nostalgia, escape, and the rich world of the imagination, ideas that are powerfully effective during times of transition. Expect to see gardens that explore fantasy, whimsy, and spontaneity within a framework of familiar garden forms.

Cleve West’s winning design for The Daily Telegraph Garden at last year’s Chelsea Flower Show is a perfect example of neo-romanticism. His sunken garden used terra-cotta columns that evoked Roman ruins. His plantings were both modern and old-world as he relied on a palette of self-seeding plants that emphasize change. The rich overlay of classical ruins in this strongly contemporary garden hinted at a world beyond, a lost history that provides a moment of escape and fantasy that make the garden delightful.

Left, design by Wirtz International; Center, Piet Oudolf's wave hedges; Right, Tom Stuart-Smith

2. Creative Hedges: One kind of revivalism that is already making a comeback is hedges and topiary. Clipping shrubs has been somewhat out of style as of late, a sort of high maintenance dinosaur of a less sustainable era. But designers such as the Jacques and Peter Wirtz, Piet Oudolf, and Tom Stuart-Smith have shown the creative potential of hedges clipped in non-traditional forms. Whether it is the Wirtz’s musically inspired hornbeams, Piet Oudolf’s iconic wave hedges, or Tom Stuart-Smith’s cloud hedge, clipped shrubs offer the potential to transform a garden space. These clipped hedges are particularly effective set against a background of herbaceous plantings. Jake Hobson’s recent book, The Art of Creative Pruning (already a best seller at Timber Press), chronicles the many ways clipped shrubs can shape a garden.

3. Moody, Expressive Plantings: This year, designed plantings will be less about color or the expression of space and more about richly evoking a mood, a feeling, an atmosphere. Think about William Turner’s sea paintings or Rothko’s floating squares of colors. Plantings will focus less on some kind of formal arrangement and more on a palette of plants that communicates a feeling, or reminds one of being in some larger landscape.

For example, Tom Stuart-Smith’s 2010 Laurent Perrier garden shows how a palette of low grasses and umbellifer flowers evokes a romantic, woodland landscape. The plantings are restrained, yet they feel like the setting for a fairy-tale. Even within the confines of a few hundred square feet, Stuart-Smith’s composition manipulates our association—our memory—of a woodland grove, thus giving his design an expansive, exultant feeling.

Laurent Perrier Garden, image from http://www.rhs.org.uk/

4. Artisanal Flourish: I predict this year garden design will focus more on artisanal, idiosyncratic details than super-sleek designs. This does not mean modern garden design will go out of style; rather, that even within the framework of modern gardens, the materials and details will rely more on warmer, artisanal constructions. This will be a reaction to both the glut of generic suburban gardens (sea of concrete pavers) and gleaming stainless-steel high end modern gardens that have become ubiquitous.

Artisanal detail: Reading nook by
Nelson, Byrd, Woltz Photo
by Eric Piasecki

5. Heirloom Ornamentals: Grandma’s favorites are hot again. As a reaction to the endless addition of over bred plants (really, do we need any more colored Coral Bells?), gardeners will turn once again to those plants that have withstood the test of time. Boxwoods and Yews, Lilacs and Hydrangeas, Peonies and Daylilies will all feature prominently in this year’s garden designs. Expect to see these nostalgic favorites even in sleeker, modern designs, too. Why should having a well-designed garden mean that we can’t have a few sentimental favorites? I’ve already noticed more niche nurseries in the mid-Atlantic region offering heirloom boxwoods or lilacs. If people are going to spend money on a new garden, they want an emotional attachment to a specific plant. Heirlooms offer just that.

In 2012, romantic is in. I predict a very good year for garden design.

Wolfgang Oehme: 1930-2011

noreply@blogger.com (Thomas) — Fri, 16 Dec 2011 03:58:00 +0000

Wolfgang Oehme, one of the most influential and brilliant plantsman of the last century, passed away today.

Wolfgang, along with his business partner James van Sweden, created the New American Garden, a strikingly original alternative to the traditional suburban yard.

Wolfgang was a personal mentor to me and many, many others. What was even more impressive than his brilliant and evocative plantings was his generosity of spirit and joy in the landscape. I plan to write a fuller remembrance of Wolfgang soon. If you knew Wolfgang and want to post a message for him, his official website is collecting those messages.

The Cloud Hedge Experiment

noreply@blogger.com (Thomas) — Wed, 07 Dec 2011 02:17:00 +0000

Lust. The first time I saw a picture of Jacques Wirtz's cloud hedges, I wanted them. Of course, I often look upon glossy magazines of European gardens and covet one thing or another. But the overgrown boxwoods that the Wirtz's clipped into iconic cloud-like shapes stayed with me. They were both solid and structural, yet light and whimsical. Artificial yet organic.

For years now, I've been thinking about using cloud hedges in a design or my own garden, but to be honest, I haven't been confident I can pull it off. After all, cloud hedges are more about garden craftsmanship than design acumen. So I was delighted when I saw Jake Hobson's new book, The Art of Creative Pruning. I hoped I would find a step by step tutorial on how to create this effect. The book unfortunately is more of an illustrative coffee table book than it is a how-to manual. The images themselves are instructive, and Mr. Hobson does give some useful advice for creative pruning. But I found his advice for creating cloud hedges to be a bit too general: " Rough out the basic forms, following the flow of the plants." So I went outside and looked at an overgrown yew hedge in my front yard. I wasn't seeing too much "flow" to work with.

One of the simplest ways to create a cloud hedge is to create one new. I recently saw this technique used by Tom Stuart-Smith in his 2010 Laurent Perrier garden for the Chelsea flower show. Stuart-Smith simply assembled a bunch of mature boxwoods into the forms he wanted for the temporary garden. A few weeks of growth and voila! Instant cloud hedge. Of course, this garden used huge mature boxwoods which probably cost the average home owner a fortune. The same effect could be done starting with smaller shrubs that eventually grow together, but this could take up to a decade before they have the desired effect. I recently planted groups of five and seven boxwoods in irregular clumps for a client. I plan to have them shaped over the next few years into these gumdrop shapes.

Large boxwoods pre-selected for the show garden, image from Chelsea Flower Show blog

Cloud hedge in its place. photo by Allan Pollack Morris

Since I can't quite afford fifteen mature boxwoods, I decided to see if I could transform the overgrown yew hedge in front of my house into a cloud hedge. My wife and I recently bought a dilapidated ranch house and were considering removing the overgrown yew hedge in favor of a more layered, softer foundation planting. However, the yew hedge--while not particularly interesting--is mature and relatively healthy. And that means we don't have to spend several hundred dollars in replacement plants.

Inspired by images from Mr. Hobson's book, I went out this weekend and started to hack at our hedge. I tried to follow the "flow" of the plant, but this hedge had been shaped as a rectangle for years, so the branching structure was pretty uniform. I started by outlining the contours or folds of the clouds, but found it hard to compose. I would stand back at the street and try to visualize some cloud-like forms, but when I got back and starting hacking, it was easy to lose the concept. I found it particularly difficult to create the amount of contrast in height that I wanted by merely shearing the plant. I didn't want to cut the yew back down to its structural branches. I've done that before and it took years before it leafed out. But I did cut it back to bare branches, knowing that it would fill out again in the spring.

I started to outline the contours or folds of the clouds which required skinning the shrubs down to bare branches in some places

I quickly came to the realization that to create the amount of contrast between peaks and valleys, I could not simply rely on shearing/subtraction alone. Instead, I would have to wait for some areas to grow out in order to get the necessary dips and valleys.

How did it turn out? To be honest, I have no idea. Right now the hedges look pretty awful. Kinda like Bill the Cat from Bloom County--some parts skinned, some parts poking out wildly. But I figure we'll see how it goes in the spring. Since we were planning on ripping these out anyways, there was no harm in trying. Hopefully, within a few years, I'll have delightfully unique, dreamy hedges to contrast with all the perennial and grass plantings we have planned in the future. Until then, our poor neighbors will have to suffer through more of my horticultural experiments.

Have any of you done any creative pruning? What's worked for you? How long did it take? I"ll be sure to post on the hedge's progress next summer.

Best New Blog: Black Walnut Dispatch

noreply@blogger.com (Thomas) — Fri, 02 Dec 2011 10:00:00 +0000

Black Walnut Dispatch, written by Virginia based gardener and garden designer Mary Gray, is one of the best new garden blogs I’ve come across in a long time. Full of heart and humor, Mary has already started an impressive number of high quality entries, from mocking oversized outdoor kitchens, to a satirical ode to L.L. Bean catalogues, to a moving manifesto about why we garden. The writing sizzles. It is like Garden Rant with a wry sense of humor. I recently subscribed by email so I won't miss a single post. Be sure to check out Black Walnut Dispatch. You will not be disappointed.

"Hot or Not" Hits the Road

noreply@blogger.com (Thomas) — Thu, 01 Dec 2011 03:09:00 +0000

This Friday December 2, I will be speaking at the fourth annual "Turning a New Leaf Conference" in Lancaster, Pennsylvania. My talk is entitled "Hot or Not: How Making Sustainable Landscapes Fashionable will Revolutionize the Movement." The talk was inspired by my original post found here.

Here is the abstract:

The sustainable landscape movement has advanced significantly over the last decade, gaining in acceptance among homeowners and designers. But many remain skeptical of sustainable practices, and there is even evidence of a backlash against using native plants. Has the push to make landscapes more sustainable hit a rut? Is the message being drowned out? How do we reach a broader audience?

The single best way to expand the appeal of sustainable landscapes is to make them fashionable. Until sustainable landscapes are shown to be beautiful, they will never be fully embraced by the American public. This talk will explore how to create a new aesthetic for sustainable landscapes that will make them more desirable. We will examine model projects that are not only ecologically productive, but strikingly original, cutting-edge designs. We will look at how the European garden scene has blended sustainability with an artistic ethos. Most importantly, we will examine strategies that CCLC members can use to create more beautiful, original, and ecologically-rich landscapes.

There's still time to register. For more on the conference, including other fascinating speakers and discussions, please visit the site's homepage: http://www.chesapeakelandscape.org/2011leaf.htm

Garden Designers Roundtable: Horticultural Idols

noreply@blogger.com (Thomas) — Tue, 22 Nov 2011 04:30:00 +0000

Plants are a particular passion of mine, but what fascinates me most is the way we design with plants. I’ve dedicated my professional life to the study of how we arrange and compose living plants. Planting design is not just about the plant as a horticultural or ornamental object; instead, it is a window into our culture, our beliefs about beauty, and perhaps most importantly, our relationship with nature.

For several years now, I’ve wrestled with what it means to develop my own style as a designer. I was fortunate enough to spend the better part of a decade working for Oehme, van Sweden & Associates, apprenticing and learning their iconic New American Garden style. Since leaving the firm in 2009, I’ve wondered how to adapt what I learned there and make my own contribution to the development of a uniquely American garden style, one rooted in the patterns of the American landscape.

It was this quest that led me to a study of the great plantsmen, designers who changed the way we think about plants. I teach a class in planting design for George Washington University, and in preparation for a lecture, I sought to select a list of groundbreaking plantsmen. Of course, one could spend an entire year studying all the great planting designers of history, but I wanted to focus on those who have most influenced the current moment. I wanted to share my personal list of ten great plantsmen, a mix of past and current designers whose designs are, in my opinion, the most relevant for today. This list includes both iconic designers of the past, brilliant contemporary plantsmen, and even emerging talent that has not been fully recognized.

William Robinson may be the most influential gardener and writer of the past two centuries. While working at a Botanical Garden, the Irish gardener and writer spent time in the wild British landscapes to collect and study wildflowers. It was in these landscapes that Robinson developed his ideas about plant composition. His iconic book, The Wild Garden, proposed startling new ideas that exploded the garden beyond bedding plants. The book gives detailed instruction about mixing hardy perennials into wild meadows, woodlands, and wet areas. The Wild Garden was not about letting a garden go, but about creating a new aesthetic that inserted tough ornamentals into wild settings.

Why Robinson Matters Today: The Wild Garden still reads like a manifesto written for today. Rick Darke’s recent republication of the book was perfectly timed. No one has yet written in such rich detail about how to create naturalistic plantings. Robinson’s ideas are fresh, original, and inspiring. Open any page in the book and you’ll find dozens of mind-blowing planting ideas. The rest of the Icons on this list owe much to Robinson.

Jekyll, a contemporary and colleague of William Robinson, was the other great British planting designer of the early twentieth century. Jekyll is best known for her collaborations with English architect Sir Edwin Lutyens. This partnership produced some of the finest examples of the Arts and Craft movement, a movement that celebrated authentic materials and craft in design. Jekyll’s background in painting strongly influenced her design style. Her borders were meticulously crafted. Using lessons she learned from Impressionistic painters, Jekyll often used subtle gradients between warm and cool flowers to effect the mood of the planting. In addition to being a garden designer, Jekyll was a prolific writer, penning 15 books that are a testament to her genius.

Why Jekyll Matters Today: No one did color better than Gertrude Jekyll. While the importance of color in the garden may have lost ground to structure and seedheads, it still matters immensely. Color is light, and no one understood how to manipulate color associations as well as Jekyll. I recently read a few of her detailed articles on design; the depth of thought and brilliance amazed me. As a naturalistic designer, I had too long ignored color, but my designs have already improved because I have used some of her design insights.

Christopher Lloyd was one of the most innovative, interesting, and masterful gardeners of the 20th Century. Lloyd lived from birth to death in a single home: Great Dixter, a 15th century house renovated by Sir Edwin Lutyens in the early twentieth century. The garden at Great Dixter was a canvas for Lloyd’s garden experimentation. Lloyd, a prolific and witty writer, revolutionized the English border by mixing tropicals, shrubs, and all kinds of unexpected combinations. Lloyd kept Great Dixter open to the public, and lived his life as one great dinner party. He was both hospitable and grumpy, but always one of the keenest horticultural minds of our time. All of Lloyd’s books are excellent, but his classic, The Well Tempered Garden might be some of the best planting advice I’ve ever read. That one book is better than 50 glossy coffee table books.

Why Lloyd Matters: Lloyd was the supreme master of the mixed border, perhaps one of the finest plantsmen of the century. His magnum opus was a 200 foot long border that he kept blooming from April to November. Lloyd’s border was legendary because of his skill in mixing plants from different habitats in the same space. Lloyd mixed large-leafed tropicals with woodland ephemerals and dry meadow grasses. What elevated this border from all other flowering borders was the way it exploited one’s associations of plants. Lloyd manipulated one’s association of a natural landscape by recalling a memory of feeling of nature, only to shatter it by adding an unexpected plant. The intentional incongruity of his plantings made you see each plant in a new and unexpected way.

Beth Chatto is the grand dame of English gardeners, the reigning heir of William Robinson, Gertrude Jekyll, and painter-gardener Sir Cedris Morris. Beth Chatto’s garden in Essex, England, is perhaps the single most influential garden of the last century. The rather modest gardener with a unique flair for underappreciated plants stirred the waters of British gardening, and as a result, sent ripples throughout the world. Begun in 1960 on a farm property that was a wasteland of "starved gravel and soggy bog,” Beth Chatto transformed the site by creating a string of contrasting yet complementary gardens. Chatto embraced the site’s difficult features and matched plants to fit the inhospitable terrain. Her garden has become a mecca for gardeners all over the world.

Why Chatto Matters Today: Though not the first naturalistic gardener, Chatto nonetheless is the pioneer—the first garden structuralist—who blazed the way for brilliant plantsmen like Dan Pearson and Piet Oudolf. “Success depends on knowledge of plant provenance and on an understanding of natural plant associations,” writes Chatto in her book The Dry Garden. Her most famous and influential garden is the Gravel Garden. Begun in 1991 as a horticultural experiment, the Gravel Garden was converted from a former parking lot. The garden has never once been artificially watered—impressive especially considering it is a beautifully blooming perennial garden in the driest part of England. While her Gravel Garden rightfully deserves the attention it has received for its sustainable approach, it is her artistry in plant combination and natural association that makes her my idol. Chatto orchestrates an international ensemble of plants into combinations that have the same resonance and harmony of a native palette. Like no one else before, Chatto understands form, color, and texture not as abstract design principles, but as an extension of a particular place.

The Dutch landscape architect Mien Ruys (1904-1999) is better known for the people she influenced (Piet Oudolf, James van Sweden, West 8) than for her own work. This is unfortunate. Ruys is the Bob Dylan of garden design. Like Dylan, Ruys’ work is distinctive, stylized, and strikingly original. Ruys grew up on her father’s perennial nursery, one of the sought after nurseries in Europe. Ruys studied landscape architecture and began experimenting by transforming her father’s land into a series of garden rooms. She went on to become one of the country’s most famous landscape designers.

Why Ruys Matters Today: If you like Piet Oudolf, you need to know Mien Ruys. While Christopher Lloyd and Beth Chatto were transforming the British garden, Ruys' work is the key to understanding much of what happened in continental Europe during the 20th century. Ruys’ designs were known for their simplicity and clarity, a combination of Dutch pragmatism, Japanese stylization, and modernism. She combined this clarity with an exuberant use of perennials and grasses. For Ruys, the large use of herbaceous plants was not merely decorative, but an essential way to experience nature in a garden. In this way, Ruys showed how planting is not just for ornament, but a way to experience space. Ruys is considered the spiritual founder of the New Perennial Movement.

If Mien Ruys is Bob Dylan of garden design, Piet Oudolf is one of The Beatles. The quiet plantsman from The Netherlands has become an international celebrity, and for good reason. Oudolf is quite simply one of the best plantsman of our time. His intricate use of perennials and grasses has captivated the world with rich tapestries of plants that are beautiful year round. If you haven't had a chance to see some of his American work such as The Highline in Manhattan or The Lurie Garden in Chicago, don't miss it.

Why Oudolf Matters: The work of Piet Oudolf reinforces perhaps the most powerful quality of great planting design: not an imitation of nature, but an artistic evocation of nature. Oudolf says, "All my work is related to trying to recreate spontaneous feeling of plants in nature. The idea is not to copy nature, but to give a feeling of nature." In an interview with The New York Times, Oudolf gave one of my favorite quotes. Looking out over his perennial meadow, Mr. Oudolf articulated it this way: “You look at this, and it goes deeper than what you see. It reminds you of something in the genes — nature, or the longing for nature.” Oudolf's goal is not merely to please the eye, but to reconnect our primal selves back to a natural world that we barely remember.

Almost two decades before Piet Oudolf was on the map, James van Sweden and Wolfgang Oehme were pioneering the New American Garden style out of their office in Washington, D.C. The architecturally-trained James van Sweden teamed with German plantsman Wolfgang Oehme to create gardens richly layered in perennials and grasses. The New American Garden takes its inspiration from the American Prairie, with spontaneous, loose, and exuberant plantings that offer an alternative to the American lawn and clipped hedges. OvS continues to do some of its best work under the leadership of its next generation of partners.

Why OvS Matters: I had worked for OvS for three years at the time I visited the Feldman garden in Martha's Vineyard, a garden whose planting was designed by Wolfgang almost a decade earlier. It was like walking through some kind of dreamscape. I remember calling my wife and telling her I had just seen the most beautiful garden I had ever been to. Wolfgang is a natural plantsman. When I would ask him about his design process, he had a hard time explaining what was so intuitive for him. But to witness Wolfgang in the field laying out thousands of perennials was to see a genius at his craft. Oehme, van Sweden is known for their huge, quilted masses of perennials and grasses, an artful expression and celebration of the ground-plane. If you have a chance to visit Chicago Botanic Garden, the work of current principals Sheila Brady and Lisa Delplace, go see Evening Island and the Gardens of the Great Basin. You will not be disappointed.

If any designer epitomizes the best of the contemporary moment, it is British gardener Tom Stuart-Smith. Stuart-Smith started doing landscape design for mostly historical properties. But starting in 1998, Stuart-Smith became a gardening rock star with a string of six gold winning gardens in just nine years, including four Best in Shows. Stuart-Smith is the link between the British border tradition of Gertrude Jekyll and Christopher Lloyd with the contintental New Wave Perennial movement of Ruys and Oudolf. If I had my choice of any designer in the world, past or present, to design my own garden, Tom Stuart-Smith would likely be on top of that list.

Why Stuart-Smith Matters: Stuart-Smith may be as gifted a plantsman as Piet Oudolf. Like Oudolf, Tom Stuart-Smith uses strongly sculptural hedges and perennials, but unlike Oudolf, Stuart-Smith continues the uniquely British emphasis on color, creating spectacular carpets of plants. No one can do moments of sheer flair like Stuart-Smith, but what impresses me more are the rich sense of place his more restrained gardens have. His 2010 Laurent-Perrier garden is at once modern and romantic. The planting feels like you stepped into a woodland glade in some fairy tale. Pure evocative power.

Andrea Cochran might be one of the best landscape architects of our time. The California landscape architect designs minimalist landscapes with maximal emotional impact. Her landscapes are inspired by modernism and by minimalist artists such as Robert Irwin who reinterpret our perception of space. Cochran's brilliant use of materials and cleanly demarcated spaces create what Mary Myers calls "a forceful sense of volumetric space." While her designs may include only a handful of plant species, this restraint creates marvelous effects. Her use of Japanese Anemones in this design or her use of native grasses in this design show what a mastery she has of materials.

My final horticultural icon goes to an emerging talent whose small but impressive body of work shows her bright future. Los Angeles landscape designer Judy Kameon creates gardens that look like Hollywood sets. Every one of her gardens is unmistakably Californian. Kameon arranges plants where each is a dramatic piece of sculpture. Lush grasses are set against sapphire blue lavenders which are then punctuated with sword-like phormiums. Most impressive is Kameon's ability to work with steeply sloping hillsides. No one in my mind can do hillsides like Kameon. She turns the vertical landscapes into sensual and expressive canvases that beckon one to explore.

What's most remarkable to me is Kameon's ability to take an international ensemble of plants--tropicals, Mediterranean herbs, desert succulents, and meadow grasses--and weave them into a palette that looks like it had evolved together for 10,000 years. Kameon's talent has drawn the attention of fashion designers, actors, and entertainers. Vogue Magazine named her one of "The Next Establishment". Her career may just be getting going, but her gift for planting is unmistakable.

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This post is included in this months' Garden Designers Roundtable. To view other posts on this subject, please check out the website: http://gdrt.wordpress.com/. And please check out the other members thought about Horticultural Idols.

Susan Cohan: Miss Rumphius' Rules: Chatham, NJ

Scott Hokunson: Blue Heron Landscapes: Granby, CT

Rochelle Greayer: Studio G: Boston, MA

Jenny Peterson: J Peterson Garden Design: Austin, TX

Debbie Roberts: A Garden of Possibilities: Samford, CT

Andrew Keys: Garden Smackdown: Boston, MA

Meaning in Landscape Architecture and Gardening

noreply@blogger.com (Thomas) — Thu, 29 Sep 2011 09:30:00 +0000

“Just as there are levels of meaning and discourse in language, ranging from laundry lists to business letters, from narrative fiction to lyric poetry, so too are there levels of meaning in landscape. They range from the mundane to the profound whether they are attractive or disheveled, beautiful or not, small or large…Landscapes are made of many diverse phenomena - visual, aural, tactile, olfactory - that may trigger the recall of things from our own personal environmental history, which in turn combine with a world of information from our education and experience. For this reason there is no question in my mind that the art of landscape design - when it is an art - is possibly the most complex and sophisticated art we possess.”

Laurie Olin from an essay in Meaning in Landscape Architecture & Gardens

Umbellifers: Selections from my Favorite Plant Family

noreply@blogger.com (Thomas) — Tue, 20 Sep 2011 09:06:00 +0000

As an admitted plant-aholic, it is pretty easy for me to fall for a plant. I have a bad habit of seeing virtue in almost every green darling. Of all of my plant crushes, one in particular stands out: I am particularly crazed about umbels.

The plant family Apiaceae (also referred to as Umbelliferae) is a family of aromatic, hollow-stem plants most commonly known for their lacey, umbel-shaped flowers. For herb and vegetable gardeners, you are probably quite familiar with many characters in this cast: carrots, parsnips, cilantro, chervil, cumin, dill, fennel, lovage, and parsley. It was the family’s usefulness for cooking that initially attracted me, but it is their striking forms ultimately seduced me.

Umbels often have low basal foliage from which mostly leafless stems arise to support striking disk-shaped flowers. From the side, the flowers look like an umbrella turned inside-out by the wind. A close look at the tiny flower clusters (umbels) is a joy in itself, as radially-symmetrical fractals reveal hundreds of sparkling blooms. Staring into an umbel, I have the same thought as I did when I gazed upon the rose window in Chatres cathedral: how can there be such exultant power in so much delicacy?

Tom Stuart-Smith's 2010 Laurent-Perrier Garden, Chelsea. Photo by Allan Pollok-Morris

Usually flowers with such intricacy lose their effect from a distance. But seeing umbels from a distance is precisely my favorite vantage point. Think about the frothy and effervescent effect of Queen Anne’s Lace (Daucus carota) tossing among a tall grass. Placed in a smaller, garden setting, few plants are as evocative of larger, wild landscapes as umbels. Their spumous blooms channel the ephemeral like few plants are capable of doing.

While I have long loved these plants, I have not gardened with them enough. Seeing Tom Stuart-Smith’s use of Cenolophium denudatum stunning 2010 Laurent-Perrier garden has convinced me of their power in designed landscapes. Stuart-Smith has the rare ability to create plantings with a dreamy, ethereal quality, but I am convinced his use of Baltic Cow Parsley gave this garden its transcendent, fairy-tale like quality.

Here are few seeds I have ordered for next year’s border. I’d love to know if any of you have gardened with them:

1. Ammi majus, White Bishop’s Weed. An annual, these showy-white flowers look like a cultivated form of Queen Anne’s Lace. 36-48” height. I plant to sow them among medium-height, ornamental grasses.

Astrantia 'Hadspen Blood,' Plant-pictures.net

2. Astrantia major ‘Hadspen Blood’, Crimson Astrantia. According to Sir James Edward Smith’s 1805 Exotic Botany, “the more refined admirers of nature” rate Masterworts as one of their favorites. Sir James, couldn’t agree more. ‘Hadspen Blood’ was introduced by the great British gardener Nori Pope. Few plants give a natural look quite like Masterworts. Plant them close to a path or terrace so their detail can be appreciated.

Eryngium yuccifolium, photo by Prairie Moon Nursery

3. Eryngium yuccifolium, Rattlesnake Master. Is there a cooler common name than that? This American native might be my favorite plant, hands down. Round, white globes emerge from strappy, yucca-like foliage. Like all members of this family, pollinators love this plant.

H. maximum, photo by Phyllis Weyland

3. Heracleum maximum, Common Parnsip. The only member of the Hogweed genus native to North America. This very tall plant has larger leaves than most umbels. Native Americans peeled and ate the young sweet leaf and flower stalks (please don’t confuse it with Water Hemlock, a deadly plant). A larval host for the Anise Swallowtail. Prairie Moon Nursery has seeds available.

4. Sellenium wallichianum, Milk Parsley. Of all the umbels, nursery owner and writer Carol Klein says Sellenium wallichianum might be her favorite. It’s easy to see why. The leaves are as nice a feature as the flowers, as billowing clumps of ferny foliage create a lacey foundation for the plant. The stems are bright red and the flowers, oh those huge, creamy blooms. E.A. Bowles, one of the great British gardeners of the 20th century, called S. wallichianum, “the queen of all umbellifers, with its almost transparent tender green-ness and the marvellously lacy pattern of its large leaves . . . the most beautiful of all fern-leaved plants.”

The One Plant Pot

noreply@blogger.com (Thomas) — Tue, 30 Aug 2011 09:24:00 +0000

Large pots are delight in a garden. Pots are perhaps the purest expression of planting design. Composing a pot is like a chef creating a salad—all of the rules of design get stripped down to their essence. In a larger landscape, the hand of the designer can be lost, but with a pot, the artificial environment is a pure display of horticultural skill.

Earlier in my career, I was obsessed with highly mixed pots. With pots, you can pull off things you never can in a larger landscape. One year, I did a theme pot of nothing but plants I found on the side of the road. It actually turned out ok. Other years, I’ve had fun combining annuals with huge leafed perennials like Tetrapanex. A well designed combination lets you see plants in a new light.

But recently, I’ve been drawn to simpler, single-plant pots. They seem to have more impact in a garden than a fussy, highly mixed pot. I wanted to share a few images of gorgeous, one plant pots from other designers:

Above: I love this composition of one-plant pots designed by Mosaic Gardens in Eugene, Oregon. I love almost anything this design firm does. Their designs are strong, yet whismical with a real sense of place and materials. My list of designers I would have design my own yard is small, but Rebecca and Buell would definitely make the short list.

http://svejo.bg/3421.html/0705home_formoverflower01

Above: The pot cluster goes modern. I love the sculptural use of plants in these simple geometric pots. Equisetum, Pinus mugo, and a purple Aeonium prove that less is definitely more.

Above: The tightly clipped boxwood in this garden define space on the terrace. The cool blue color of the pots contrasting with the deep green of the boxwood is utterly elegant.

Above: Is it really this easy? Boxwood, a dwarf spruce, and terra cotta prove that boring foundation plants placed in a great pot can transform a space. Image from Siebert and Rice catalogue.

Photo by Valerie Easton, garden design by Nancy Heckler. Originally published in Pacific Northwest Magazine

Above: Edible and ornamental? This simple pot of rosemary set in front of Redbor Kale proves that moving a pot from the terrace to the garden can be a wonderful way of punctuating a moment. Check out the full article of this delightful garden.

Want great pots for simple creations like this? Here are some of my favorite sources. First, for fiberglass recreations of large size pots, I always use Capital Garden Products. This company is able to patina fiberglass to look like aged terra cotta, lead, or even bronze. Fiberglass is a super-strong, super light weight alternative to terra cotta, lead, or metal planters.

For smaller, terra cotta pots, I love Guy Wolff. My wife and I visited his potting house a few years ago in Connecticut. He specializes in recreations of historic pots. His line is very affordable and very beautiful. My favorite are his white pots. They show off plants marvelously.

A photo I took of Guy Wolff in action

When Metaphor Fails

noreply@blogger.com (Thomas) — Mon, 15 Aug 2011 23:20:00 +0000

This year, my wife and I made a token attempt to start a garden. We managed to pull ourselves away from the home renovation long enough to carve a perennial border out of a piece of our side yard.

Right now, it looks like a tattered tapestry. Some perennials have established with athletic vigor, while others lie low, perhaps waiting till next year. I’ve seeded the holes in the border with summer annuals, which have quickly taken advantage of their slower to establish neighbors. The riotous color and size of the annuals have eroded what bit of compositional clarity that initially existed. Weeds run rampant throughout. Crabgrass, Bermuda grass, and Bindweed dominate the area where we plan to add a stone path and terrace. They control territory like a Mexican drug cartel. With so little time for the garden, the weeds and I maintain an uneasy détente—they have their territory, and I have mine.

Already I’m making notes about what needs to be changed. Too many filler plants, not enough structural ones. Needs more upright spires. Dot in a few architectural shrubs. Add low, dark-leafed annuals along the edges for contrast. Too many thin, linear masses: re-mass perennials in block-ier, thicker masses. The list grows by the day.

August crushes my idealism. All winter and spring I made pretty pictures of the garden in the soft light of my mind. In May, these images felt almost attainable. But August is the ultimate judge; the glare of the midday sun bears upon me the inescapable force of reality. All prior imaging disappears with the dew. The garden is simply what it is.

Realism is the theme of my summer. Last month my father went through a complicated open-heart surgery and began a miraculous recovery from a stroke. Seeing him suffer through an intense recovery has also confronted me with a jarring reality. With a recovery like his, nothing goes the way you expect. With every hurdle he overcomes, another battery of complications sprout up. He has faced his recovery with a strength and grace that is indescribable unless witnessed. The man I knew as the sweetest man on earth has proved to be one of the strongest.

It is times like this when reality itself overcomes our ability to process it in words. When tragedy strikes, I find myself instinctively trying to cloak it in metaphor, to find words to distance me from the experience itself. But the firmness and weight of that reality causes metaphor to fail. What analogy is there for watching someone you love suffer? What platitudes? I was recently reading an account of a father, writer Aleksander Hemon, who lost his ninth-month old daughter to cancer. During her illness, he described, “Isabel’s illness overrode any form of imaginative involvement on my part. All I cared about was the firm reality of her breaths on my chest, the concreteness of her slipping into slumber as I sang my three lullabies. I did not want to extend myself in any direction but hers.”*

Since my father’s surgery, I find myself directing the affection I feel for him more urgently toward my eleven-month son. It is my way of bridging the distance. As Jude slips into sleep, I brush my fingers across his temple and channel a prayer for my father. It is the only prayer I ever really mean: please, please, please. The precious beating heart in front of me is linked to the precious healing heart of my dad in a sea of my confused, inadequate love.

After my son has gone to bed and the dishes have been washed, I step outside to the garden. The sun is setting, and I make a half-hearted effort to pull a few weeds. For a moment, I squint my eyes and try to recall the image of what I thought this garden would look like. But I can’t remember. All I can see is what is here.

* The referenced article was written by Aleksander Hemmon, “The Aquarium,” The New Yorker, June 13, 2011, pg. 50.

Beyond the Border 4: Maintaining Perennials to Last

noreply@blogger.com (Thomas) — Wed, 10 Aug 2011 09:12:00 +0000

This is the final post in a series I’ve been doing on how to design perennials and grasses in landscape settings. By landscape settings, I’m referring to non-garden sites, including public parks, commercial and institutional landscapes, or even residential sites larger than a single bed. Throughout this series, I’ve made the claim that herbaceous plants—the most dynamic and expressive plants a designer can use—ought to be used more often in our built landscapes.

My last post talked about how to select plants for these low maintenance sites. This post will focus on the single greatest reason people avoid using perennials and grasses: uncertainty about how they should be maintained. Almost every time I suggest using herbaceous plants in landscape settings, here’s what I hear: perennial plantings are fussy and high maintenance; clients don’t understand them and won’t take care of them; in a year from now, it will all be a weedy mess; use more shrubs or lawn.

It kills me. Some days I wonder if I will spend half my career battling the tyranny of low expectations.

The reason it kills me is because I know from experience how low maintenance perennials and grasses can actually be once established. I know that clients can have a lasting, beautiful, and sustainable planting in a fraction of the time it takes to maintain a lawn.

To understand how to maintain perennials and grasses, one must first understand a few basic concepts:

1. “Low Maintenance”: Those are perhaps the two most misunderstood words in the landscape industry. In today’s landscape industry, they are code words for “do nothing” or “I don’t have to care.” Landscape professionals promise this to clients, and clients expect this as a result. The low maintenance landscape is the holy grail of the industry. Plant breeders breed plants for fewer inputs, retail nurseries only keep inventory of proven plants, and contractors and designers stick close to their small palette of tried and true plants. It is a self-perpetuating cycle.

Of course, this is a mythology. Without maintenance, almost any designed landscape will fall apart. The cruel irony of maintenance is that to reap the benefits of a low maintenance landscape, one must first heavily maintain it until it is established.

2. “Once Established”: This is perhaps the most critical concept to developing a planting that lasts. An established plant is one that is fully rooted, adapted, and growing in the native soil. For perennials and grasses, the establishment period is typically two to three growing seasons from the time of installation. An established planting requires dramatically less water, less weeding, and less overall care than a new planting.

3. Client Buy-In: Without a doubt, the most important thing you can do is to come to make the owner aware of the maintenance before you plant. When I meet with clients, I describe in detail the weekly requirements of a new planting. I try to fit the landscape to what they can afford to maintain. But if you can invest them in the process, the results will be remarkable. Every good relationship I’ve had with a client, the landscape thrives. Every mediocre relationship produces mediocre landscapes.

Ok, what about the specifics? Getting plants to establishment requires three basic tasks: watering, weeding, and re-planting. Each of these concepts is relatively simple. The question is: how often and how much?

Watering

Plants need water. One would think this is a non-controversial statement, but more and more often, I find clients—particularly those interested in green design—surprised that they have to water. “Isn’t it drought tolerant?” “Isn’t watering wasteful?” Or my favorite: “Can’t you just specify me some plants that don’t need to be watered?”

Even drought tolerant plants need water. “Drought tolerant” is another phrase that makes me antsy. Like “low maintenance,” “drought tolerant” is code for I-don’t-need-to-ever-water-it. Though some plants like it dry, no plant likes drought. Even if a plant survives drought, they rarely thrive. Regular watering is a signal to a plant that it’s ok to grow and flower, whereas drought is a signal to cut back.

S. Aitken

By all means, choose plants adapted to your region’s average rainfall. But until the plant is established, count on regular watering, at least one inch of water a week, perhaps two during the heat of summer. Why? Typically, nursery plants are potted in a lightweight potting medium. In a nursery they get watered daily, and fertilized quite often. So when they are planted, they must adapt from growing in a soilless bark medium with heavy external inputs, to heavy soils with little external inputs. This is quite a transition. Watering allows the plant to make this transition. I also believe in fertilizing young plants during the early growing season with an organic, nitrogen-rich fertilizer. Do not fertilize during the heat of summer or during a prolonged dry-spell.

What about irrigation? I am a fan of any system that makes it easier to take care of a planting. Drip irrigation is the most efficient form, but pop-ups are often easier to maintain. If you decide not to irrigate, consider temporary irrigation. Just make sure that the plants get watered regularly until they are established.

Weeding

Newly disturbed soils must be weeded. The good thing about perennials and grasses is that they grow so quickly, often shading or crowding out weeds even within the first growing season. Plant spacing makes a difference in weed control. If the client can afford it, I try to space perennials and grasses 18” on center (average—this depends on the plant). Twenty-four inches on center works well for most landscape perennials, but this spacing will require more initial weeding. How much time should you budget for weeding? Roy Diblik, co-owner of Northwind Perennial Farm and author of the book Small Perennial Gardens: The Know Maintenance Approach. Diblik states that his gardens require an average of 15 to 20 minutes of maintenance every 10 to 14 days. That’s considerably less time than it takes to mow most lawns. Here’s my conversion rate for larger landscapes. For every quarter acre of planting, assume a three man crew for two hours at least three times a growing season. You can scale that ratio up or down depending upon the size of the landscape.

Re-Planting & Transplanting

Begonia grandis (foreground) did not come back in this garden, so the Hakonechloa was expanded to fill in the hole

This is the one that surprises most people. Successful planting installations require occasional re-plantings. I typically estimate that 5-10% of the total planting will need to be replanted after the first year. No matter how well you know your plants, no matter how well you studied the soil and the exposure, some replanting is typically necessary. This is most important one year after the initial installation. Some replanting at the second and third anniversaries will help ensure that lush, full plantings continue.

A Different Mindset

Maintenance is not a bad word. Maintenance is gardening, a personal investment into the landscape. The initial planting is just the beginning of the story, not the end of it.

This series is dedicated to the proposition that our built landscapes can be more than they currently are. Perennials and grasses are largely absent from our public, commercial, and—to a large extent—even our residential landscapes. These plants are the most dynamic, most ephemeral, and most expressive plants available. They have the ability to transform stiff public spaces into lush, living landscapes.

As a culture, we’ve learned to maintain ridiculous expanses of lawn. We’ve developed special machines that cost hundreds of dollars (mowers, edgers, trimmers) and expect that every landscape must have one. We expect these landscapes to be maintained every week or two during the growing season. When you think about it, we’ve chosen one of the highest maintenance landscapes possible—the lawn-- as our national landscape.

Don’t listen to the bush-pushers, those jaded contractors or city officials who tell you that shrubs and lawn are the only things that can be maintained. We can have richly layered tapestries of perennials and grasses as a part of our everyday landscapes. But it will require a different mindset. And it will require different maintenance approaches. But the end product is worth it.

Native Plants & The Wild Look: An Argument for Design

noreply@blogger.com (Thomas) — Thu, 04 Aug 2011 23:15:00 +0000

Marcus de la Fleur's design for a residence using native plants prompts the question: does using natives in wild patterns help or hurt the native plant movement? Image by Marcus de la Fleur

I have a conflicted relationship with wildness.

When I think about the sea of lawns and generic plantings that dominate our built landscapes, when I reflect on how quickly our native woodlands are disappearing, I yearn for more wildness. In many ways, our landscapes are too tidy. Our shrubs are too clipped, our lawns too manicured, our planted spaces too restrained. Despite recent progress with more sustainable gardens, the McLandscape is still the dominant form in our country.

"Yard of the Month"

Just to get a sense of what’s considered beautiful in our country, try this experiment: do a Google image search for the phrase “yard of the month.” The aesthetic is clear: tightly clipped evergreens smashed up against the house, an endless expanse of weedless lawns, and—for landscapes with a special flourish—a floating bed on annuals around the mailbox or a tree.

So in this context, wildness is desirable. How liberating is it to banish lawn altogether from one’s yard? How delightful is a project like the Highline that has an elevated meadow that winds between skyscrapers? How welcome are spontaneous, self-seeding wildflowers in an institutional landscape? Wildness adds an element of drama and dynamism sorely needed in our landscapes.

While I praise wildness on the one hand, I am concerned that it has become the de rigueur of native gardens these days. It is as if a native garden, by definition, must be wild and sprawling. To create a native garden is not only a statement against exotic plants, but it is a statement against traditional garden forms altogether. Almost all of the sustainable landscape techniques, including rain gardens, bioswales, and green roofs—have adopted a wild aesthetic.

So what, you might ask? Don’t we want to import not only native plants to our built landscapes, but the patterns and forms of our native landscapes? Yes, but I want native gardens to embrace a diversity of design styles. I have a couple of problems with a “natural only” look.

An advertisement for native planting, or an argument against it? Rain Garden. Photo and design by Marcus de la Fleur

First, designing a garden or landscape with a wild look takes quite a bit of effort and planning. There’s a difference between a carefully crafted wild look and sloppy planting design. Too often, sustainable landscapes emphasize plant selection at the expense of overall composition. Plants are not massed, so they don’t have visual impact. Small wildflowers are placed next to towering prairie plants, creating a chaotic scene. Lines, form, and order are banished, so all sense of relationship to existing structures is lost. Herbaceous plants are often placed too far apart. In our effort to imitate nature, we’ve turned our back on the forms and meaning of 4,000 years of garden history.

I was recently reading Christopher Lloyd’s book Succession Planting for Year-Round Interest. Lloyd was one of the last of the great British border designers, a person rigidly trained in the horticultural arts. In it, he chronicles how he maintains year-round color the legendary border at Great Dixter. What was remarkable to me was how much effort, art, and skill it took to create a border with year-round interest. A thought occurred to me: have we as a culture lost these horticultural skills? Or even still, did we ever have them?

In my dreams, if I were to create a curriculum for future sustainable gardeners, I would have them first spend a year studying and drafting the great gardens of history. They would study the geometry of the Egyptians, Persians, and the Greeks; the proportions and perspectives of Italian renaissance villas; the craft in combinations mastered by the Arts and Crafts gardens; and the asymmetry of the great modern gardens. Only once they were proficient in these forms, could they create naturalistic landscapes. Before you break the rules, you must first know the rules.

My second problem with the wild look is my fear that we’re turning the public away from using native plants. When native plants are associated with a wild, chaotic landscape, we narrow their potential adoption in built landscapes. Yes, I do think the American public needs to adopt an aesthetic that permits a bit of wildness, spontaneity, and heck—even a bit of sloppiness. But the way to do that is not to replace our front lawns with a tall grass prairie. We do that by creating native gardens in that fit into traditional or contemporary garden forms.

That might mean placing naturalistic planting within a clearly defined framework. Even the reigning king of naturalism, Piet Oudolf, uses clipped hedges and lawn to set off his herbaceous plantings. It might mean using some native cultivars that are more compact and colorful bloomers. It might mean that we keep lawn in some contexts, though smaller, more defined, and less manicured. It might mean creating highly artificial lines and edges to make sustainable gardens related to its built environment.

Even a naturalistic designer like Piet Oudolf sets his naturalism within a strong formal frame that relates it to the build landscape. Image and design by Piet Oudolf.

The art of native gardens is not in how well we imitate nature, but in how well we interpret it. Native gardens can still reference their community of origin; in fact, it is better that they do. But when we reference nature, it should be a clearly abstracted, stylized version of that plant community. Dotting wildflowers together just like you saw them on your hike is arbitrary when you do it in your backyard. What does it relate to? We give it meaning in human landscapes when we take natural pattern and connect it to the built environment. Distilling the essence of native landscape patterns and applying it to our yards, streetscapes, and parks is no easy task. But it is an art worthy of pursuing.

Roberto Burle Marx used plants from his native Brazilian rainforest, but he abstracted them into distinctly modern, artistic patterns. His work is one model of how native plants can be used in contemporary landscapes.

Beyond the Border Part 3: How to Select Plants for Landscape Settings

noreply@blogger.com (Thomas) — Wed, 13 Jul 2011 01:11:00 +0000

This is the third post in a series I’m doing on perennials and grasses in the larger landscape. I’ve made the claim that perennials and grasses—possibly the most dynamic and interesting plants a designer can use—ought to be used more often in our built landscapes. Imagine our public landscapes, yards, and office parks cloaked in a rich tapestry of sustainable and beautiful perennials and grasses inspired by the patterns and palettes of our native vegetation.

My last post talked about a compositional strategy of massing plants in order to reduce their maintenance and increase their legibility. This post will focus on the second strategy: how to choose the right plants. Plant selection is absolutely critical to the long term success of a planting, and to be honest, it’s not easy. Here are some general strategies that can help.

What Plants Do I Choose?

Choosing the right plant for the right spot is hard enough. With every site, there is a dizzying list of cultural requirements (exposure, slope, soil, climate) that one must consider. In a larger landscape setting, there are additional design factors to consider.

1. Filler Plants to Create Volume

Aster oblongifolius creates volume against a drive.
Design by Ching-Fang Chen

Large perennial and grass beds are most attractive when they create volume against a void, such as a lawn, path, or street. Let me share a secret with you. Great perennial planting in landscape settings is not about perfectly balanced flower colors—though color matters. It’s not really about creating great photogenic combinations—though combinations add style to a composition. Half the battle in creating herbaceous plantings that endure is to simply cover the ground at a relatively uniform height. If you can find perennials and grasses that thickly carpet the ground and range in height from 12-42 inches, you're halfway there.

In his books and interviews, Piet Oudolf talks much about the distinction between structural and filler plants. This distinction is key to his compositions. A structural plant is one whose form is distinctive and architectural, whereas a filler plant has a more amorphous, cloud-like form. Consider the strongly structural flowers of an Echinacea or an Echinops. In a composition, the eye will fall onto these distinct forms. These plants also tend to dry into distinctive seed heads in the fall and winter, creating enduring interest through the year. Filler plants include most ornamental grasses (Switchgrass) and many mounding perennials (Asteromea mongolica). Oudolf recommends using a ratio that heavily emphasizes structural plants to filler plants, around 70/30, mostly to make sure the composition has strong form throughout the year.

My advice is to reverse that ratio. Of course, Oudolf’s work is undeniably beautiful and masterful. But I have two problems with using that many structural plants in landscape settings. First, structural plants tend not to cover the ground as well as filler plants. So when they’re not maintained well, it creates gaps where weeds can fill in. Second, since structural plants are more about a distinctive profile of a flower or leaf, they tend to have shorter bursts of interest. Yes, they look great in winter, but there are moments in early spring, for example, when they’re wiry or just not as full.

Find a palette of perennials and grasses that quickly cover and carpet the ground, and then mass them in large groups. Think about perennials or grasses you’ve seen that are vigorous, thick coverers. Ornamental grasses fill this role beautifully, so for landscape settings, consider using them as a higher percentage of the total composition than you would in a border (around 30-50%). Densely-matting perennials such as Aster oblongifolius, Solidago ‘Fireworks’, Asteromea mongolica, Persicaria amplexicaulis, Pycnanthemum muticum, and others should be the basis of your palette. Your base palette should be perennials that have year-round volume, not necessarily year-round blooms.

If your composition uses mostly filler plants, won’t it be just an amorphous blob? The key to creating dynamic visual interest with filler plants is create contrast between massings.

2. Create Contrast between Massings

The second plant selection strategy is to create sharp contrasts between masses of plants. Oudolf’s distinction between structural and filler plants is his way of creating contrast in highly interplanted designs. However, if you use large masses of perennials, the lines between the masses themselves create contrast. It takes some of the effort out of the design process. Instead of trying to contrast every 10 or 12 plants, you have to contrast every 100 or 200.

Since filler plants tend to be more amorphous in form, it’s important to contrast texture or flower color from mass to mass. A fine textured Switchgrass, for example, should be contrasted in the adjacent mass with a coarser textured Persicaria or a shrub rose. Structural perennials should be used, but in smaller pockets that get repeated at the edges of the larger masses. See the diagram. The 'S' indicate structural perennials. This strategy emphasizes the volume and ground-covering strength of filler perennials, while using structural perennials as accents that get repeated throughout.

3. Incorporate Low Woody Shrubs

Rhus aromatica 'Gro-Low' forms a dense mass

For long-term reliability in large, low-maintenance landscapes, you have one more resource available to you. The use of low shrubs (36” or less) can be a way to add texture, reliability, and interest to your landscape. I’m not talking about those awful carpeting junipers, crimson barberries, or sprawling euonymus that get scattered all over strip mall parking lots. Instead, use a palette of soft, loose, and flowering shrubs that accent perennials. Some of my favorite low shrubs include Caryopteris, shrub roses, Clethra, Aromatic Sumac, Spiraeas, and Itea. Low evergreen shrubs like boxwoods or laurels are can also anchor aspects of the design.

If you use low shrubs, the trick is to choose plants that are loose in form and compact in height. Newer cultivars expand our options to shrubs that once were large and sprawling.

Plant selection is never easy, and to be honest, requires a good bit of trial and error. But if you pay attention to perennials that are vigorous, compact, and have year-round volume, you’ll start to develop a palette and technique that can be applied almost anywhere.

Next post: Beyond Installation—What is required to make perennials and grasses last?

Beyond the Border Part 2: Massing Matters

noreply@blogger.com (Thomas) — Fri, 08 Jul 2011 09:30:00 +0000

The same rules that create impact and drama in art can be applied to perennial planting.

My last post set up my proposition that perennials and grasses—the most dynamic plants a gardener can use—ought to not only be used more often, but used in as a larger percentage of our built landscapes. It’s time to liberate perennials from the confines of the British border and embrace a new aesthetic inspired by the patterns and palettes of our native vegetation.

This post will ground my lofty rhetoric with some practical how-to advice. How do you design for long term success with plant material that is inherently ephemeral? To achieve lasting, low-maintenance perennial gardens, there are two areas one must master: composition and plant selection. This post will focus on the first, and most important, rule of composition: massing.

First, let’s understand the context we’re discussing. Perennials in a landscape setting (parks, civic landscapes, large residential) are inherently different than a flower border. They are larger in area, typically set farther away from the viewer, and are not gardened as intensively. So the rules of composition must address this context.

Massing Matters

More than any other strategy, massing perennials and grasses together is the golden rule for landscape perennials. Why? We group several of the same plants together in order to make them more legible and give them visual impact. A single flower in a half-acre planting disappears; but a block of 100 (residential), 200 (small park), or 500 (large park) has dramatic impact even from a distance. Massing perennials together draws attention to their ornamental characteristics. It amplifies their color, form, and texture. More importantly, it also helps relate the scale of the plantings to the scale of a house, building, or park. A mass of 20 Echinaceas, for example, can look paltry next to a monumental building. Massing plants together gives the planting proper proportions to their context.

Larger massings of sedges and perennials in a biofiltration garden for an office park. The lines between the species create a pleasing composition. Design by Ed Hamm for Rhodeside & Harwell. Photo by Thomas Rainer.

The European ‘New Wave’ style made popular by designers like Piet Oudolf, Noel Kingsbury, Michael King, and other celebrated designers tends to interplant perennials in smaller clusters to create highly textured tapestries. I am personally a huge fan of this look, particularly to see it executed on large public projects like the Highline and Lurie Garden in Chicago (even Oudolf masses plants together for effect). These designers use repetition rather than massing to give their compositions visual coherence. However, in my experience, the main drawback of a mixed meadow approach is that it requires quite a bit of maintenance, particularly in the heat and humidity of the eastern U.S.

Massing reduces maintenance. By placing plants of the same species together, you group them by their cultural requirements. Everything within that block needs the same care. It also makes weeds much easier to identify. In highly mixed plantings, identifying a weed from a young perennial or grass requires a trained gardener—a luxury not available in most landscape settings. Massing also makes it easy to re-plant if a perennial dies or struggles. Every project I’ve ever worked on required re-planting anywhere from 3-10% after the first year or two. With large masses, it’s very clear what needs to be replanted.

A nicely interplanted moment, but with five species in just a few square feet, the perennials are already competing for light and nutrients. To keep this composition together would require quite a bit of maintenance.

Massing plants of the same species together also reduces competition between perennials. Any time you mix species, the plants compete for light, water, and nutrients. All of my early experiments with interplanting perennials went poorly as one plant often “ate” another. The composition grew together, the more aggressive plants eliminated their more demure counterparts, and the end result was a total mess. On one project where I interplanted about ½ acre of perennials, I went back a year after it was installed and had to un-interplant the entire garden. The garden had grown together in this awful mess. Anything that was mixed together was pulled out and separated. The correction worked. I’ve visited it several times in year two, three, and four. The masses are more readable, the maintenance staff can easily identify weed from desired plan, and the garden is more stable.

Since then I’ve had a good bit more success with interplanting perennials, but it requires much more planning, horticultural knowledge, and care with plant selection than I initially understood. I’ll discuss some simpler strategies for interplanting later. Even though I interplant quite a bit now, it is still within the context of larger masses.

Two images of a garden designed by Wolfgang Oehme that feature large
perennial masses appropriately scaled for the residential setting.

My early mentor, Wolfgang Oehme, of the design firm Oehme, van Sweden & Associates is a huge proponent of large-scale massing. Wolfgang is one of the great plantsmen of the last century, and his success in using this richly layered style of large perennial masses validates this method. Since I’ve left OvS, I’ve had an opportunity to experiment with refinements to this style, particularly a method of matrix planting. It blends all of the advantages of large masses (maintenance, legibility) with a more visually dynamic field. More on that later.Next post: What type of perennials and grasses do I choose? Some tips on choosing worthy plants for landscape settings.

Beyond the Border: How to Use Perennials and Grasses in Landscape Settings

noreply@blogger.com (Thomas) — Wed, 06 Jul 2011 09:30:00 +0000

Of all the plants I frequently obsess about, herbaceous perennials and grasses are perhaps my favorite. Of all the plant categories, they are the most ephemeral, dynamic plants. One can mark the seasons with these plants; they are harbingers of change. And as a designer, perennials and grasses are the most expressive plants within my palette. Rich layers of bold perennial massings can express a site in powerful ways.

The British border

When it comes to designing with perennials and grasses, however, we have a limited language for their use. The perennial border—an intricately arranged, delicate frame of flowers—is really the only concept we have for their use. And while borders can be beautiful, they have limitations. They are generally high maintenance, fussy, and require a high degree of horticultural knowledge. As a result, American gardeners and landscapers are often hesitant to use perennials and grasses because we associate them with British-styled borders. But it does not have to be this way.

Let me propose an alternative. Instead of limiting our landscapes to two distinctly British genres (the manor lawn and the perennial border), let us take the border and explode it out of its box. Let’s blanket our landscapes in bold massings of perennials and grasses. Let’s convert our wall-to-wall carpeting lawns into well-proportioned area rugs surrounded by perennials and grasses. Let’s drape office parks and civic landscapes in vibrant tapestries of flowers, ferns, and sedges.

The American landscape—from the great forests of the East Coast, the iconic prairies of the midland, and the mountains, deserts, and forests of the West—should be ample inspiration for a new, distinctly American garden aesthetic. Like the American landscape, let us use no small gestures. Let us draw on our country’s rich native palette and patterns and distill them into artful, garden spaces. The New Style will not merely imitate our natural landscapes, but interpret them into uniquely modern, human landscapes.

Over an acre of herbaceous plantings added in the right of way in
downtown D.C. Designed for NOMA BID by Thomas Rainer, Derrick
Wolbaum, & Elliot Rhodeside, Rhodeside & Harwell.

Ok, Thomas, enough with the manifesto. Is it really practical to use herbaceous plants on such a scale? Won’t planting huge swaths of perennials and grasses require an enormous effort of weeding, watering, and gardening?

The short answer is yes in the short term, but in the long term, this style of planting can be very low maintenance—even less maintenance than lawn and shrubs. The key to successfully planting large scale perennials and grasses is to combine good plant selection with smart massing.

In the next couple of posts, I’ll get into the nitty-gritty of how to select perennials and grasses for landscape settings. What types of perennials and grasses are best for larger massings? How do you arrange them in a way to minimize their maintenance? How do you make these landscapes full, beautiful, and lasting?

Stay tuned . . . I’m giving away all the secrets . . .

Gardens and Memory

noreply@blogger.com (Thomas) — Wed, 29 Jun 2011 09:30:00 +0000

Photo of Reservation 232 taken in 1927 (photo courtesy of Historical Society of Washington)

Gardening for me is mostly a solitary activity. But the last few months, I’ve been sharing my watering, weeding, and transplanting with my ten-month old.

It gives my wife a few moments of peace, and it is a pleasant distraction for Jude, who would otherwise be tugging on an electric cord or grubbing dust balls from underneath the refrigerator. Jude is fascinated with the ornery mockingbirds (“dta” while pointing), the cloud of bees over our perennials, and the raisiny fruit on our Serviceberry tree. He often notices something that I do not. Yesterday, he leaned over to grab the seed clusters of our Kousa Dogwood. They had budded into these gorgeous emerald orbs. “Huh,” I thought. “That’s cool.”

Image by Fred Jeranes

To see the garden with my son changes the way I experience it. The filter through which I see the garden is dislocated, and I not only see the garden in a new way, but see my son as well. I get these glimpses into his precious mind, experiencing the world all fresh and new.

Moments like these make me think about other gardeners. If I feel most like myself—most grounded—while I wander through my garden, then I want to know other gardeners as they are in their gardens. How do they see their gardens differently than I do? What do they care for and love?

Kim Breneger

Several months ago, I was contacted by a woman who is working with a group to create a memorial garden for Kim Brenegar. Kim was a garden designer who lived and practiced in the Capitol Hill neighborhood in Washington, D.C. Kim died at the age of 49 in a tragic car accident. Although I never knew Kim personally, her presence was everywhere in the neighborhood. Friends of mine were her clients, and they raved about her. Kim was passionate and colorful gardener and designer. I only knew people who knew Kim, but her enthusiasm was infectious. Her loss was not just for those who loved her, but the entire neighborhood and gardening community in Washington, D.C.

The Friends of Kim Brenegar have proposed a most fitting memorial. Together with the D.C. Department of Parks and Recreation, the Friends group will redesign, restore, and maintain a garden called Kim’s garden on the site of a National Park Service Reservation at the intersection of 8^th Street SE and Independence Avenue that Kim volunteered her time to maintain.

This garden will be an ideal tribute to Kim. What I love most about this project is not just the physical space—the garden—dedicated as a memorial, but that volunteers and friends will remember Kim through the act of gardening. It’s not so much the place that is connected to her memory, but the activity of caring for the garden as Kim did.

We are what we love. To connect with another, we must love what they loved, care for what they cared for, and cultivate what they cultivated. In doing so, we get a glimpse of the heart.

To read more about Kim’s Garden, click here.

Native Combinations: Late Summer Glory

noreply@blogger.com (Thomas) — Tue, 14 Jun 2011 09:30:00 +0000

Pink Muhly Grass (Muhlenbergia capillaris) has seduced garden designers for the last decade. Its haze of hot pink inflorescences set the late summer garden ablaze. But unlike other ornamental grasses, it is a surprisingly tricky plant to design with. Muhly Grass does not offer the same early season mass and volume that Switchgrass and Fountain Grass provide. In fact, through most of the summer, it sits low and wiry—barely substantial enough to cover the mulch. I planted a large mass of 120 plants beside a path in a southern garden I designed. The result was rather disappointing. Until August, it looked rather weedy and insubstantial. Once it bloomed, the effect was glorious.

Muhly Grass in early summer is rather uninspired

So to avoid Muhly Grass’s spring and summer doldrums, use it in combination with other plants. I now use it almost like a bulb or other ephemeral. Plant it along the edge of the border next to other fuller edge perennials. Or drop it inside the front of the border and let it disappear in other perennials until it blooms. One of my favorite combinations I saw at the U.S. Botanic Garden’s National Garden. They combined Pink Muhly Grass with a dwarf cultivar of the native Swamp Sunflower.

Helianthus angustifolius‘Low Down’ is a fantastic cultivar of a truly underused native. Low Down Sunflower offers narrow, black-green foliage at a height that is more suited to the average garden. While the straight species reach a sprawling seven feet tall, ‘Low Down’ stays between 2-3 feet high. The plant is literally blanketed in flowers from late summer well into the fall. The blooms are great for cut flowers. And while it is native to moist soils, this plant does well is average garden soils.

Low Down Sunflower is perfect in combination with Pink Muhly Grass. Both share light, narrow foliage, but the Sunflower adds mass and volume in the spring and summer—when Muhly Grass is rather boring. And in late summer, each plant explodes in bloom. The Muhly Grass covers the dense Sunflowers in a pink mist. Each plant is a show-stopper, but the combination is truly captivating. Both plants do extremely well in the hot and humid southeast and midwest--areas that often challenge perennial gardens.

Helianthus a. 'Low Down' combined with Muhlenbergia capillaris at the U.S. Botanic Garden

When I hear someone say that natives are not quite as showy as exotic plants, this combination often comes to mind. Our imaginations are the only limit to the potential of native plants.

2011 Topic List for Speaking Engagements

noreply@blogger.com (Thomas) — Fri, 03 Jun 2011 17:43:00 +0000

I occasionally get requests for to speak to garden clubs, public agencies, or other groups. I love nothing more than talking with other interested gardeners, designers, plant geeks, and landscape architects. I've just added a page to this blog that list topics that I have already developed talks for. I've attached a link to the sidebar called "Talks."

http://landscapeofmeaning.blogspot.com/p/talks.html

The Best Planting Tip I Ever Received

noreply@blogger.com (Thomas) — Wed, 01 Jun 2011 09:25:00 +0000

This spring my wife and I started to convert the expanse of lawn around our newly purchased ranch house into gardens. While we focus on renovating the insides of the house, the focus for our garden is its infrastructure and bones. To that end, we’ve been smothering several hundred square feet of lawn under cardboard, newspapers, and compost; planting young shrubs to create screens; carefully carving specimens out of overgrown trees; and generally preparing the soil for future garden spaces. Last week we installed several hundred perennials and grasses on the side of our house. During that planting, I remembered the best planting advice I’ve ever received.

This advice came to me by way of a representative from Monrovia Nursery. Monrovia is one of the sleeker national nurseries with big ad budgets and relentless branding strategies. While I’m typically turned-off by glossy national nurseries and their patented plants, I must admit that Monrovia knows their stuff when it comes to installing plants.

A root bound container plant. Image from Virginia Cooperative Extension

The advice focused on techniques of installing container plants. The big problem with container plants is that they get root bound. Roots naturally grow out and down (mostly out) away from the plant. When the roots of a plant in a pot reaches the wall of a pot, it has nowhere to go and will begin circling the perimeter of a pot over and over again. Almost any gardener who has brought home a new plant from a nursery has seen how a container plant can get root bound. It’s best to avoid plants in this condition, but often gardeners don’t have that option.

Roots of a Panicum plug.
Direct them away from the
plant before planting.

I had known how to direct the roots away from the plant using a root hook, or by scoring the sides of the roots with a sharp blade. However, what I did not realize was that root bound plants often become so dense, they will not absorb water. The density of tangled roots in a container plant can make the plant hydrophobic—it literally sheds water. Think about a dry sponge. When you first stick it under the faucet, water bounces off of it. So if you simply place that root bound plant in the ground and water it, water will more than likely run off the root ball and move toward the less dense soil around it. Even if you water it, the plant may not be getting the water.

How do you deal with this problem? The idea is to soak the plant for several minutes in water prior to planting. When you plant, fill up a large bucket with water--preferably rainwater since it does not have any of the chlorine or other chemicals of municipal water. Take the plant out of its pot and gently pull any encircled roots away from the plants. Then set the root ball in the bucket of water. Let it soak for anywhere from 30 seconds to three minutes—or until air bubbles stop coming out of it. This deep hydration actually reverses the plant’s hydrophobia. When you install a sopping wet root ball into the ground, the dry soil around it actually clings to the root ball by osmosis, creating a better soil to root contact. This technique is especially good for container trees. If the plant is that large, consider filling a wheel barrow full of water.

Here I'm soaking the Panicum
in compost tea prior to planting.

Want to really baby that plant? Here’s my own little spin on this trick: soak the root ball in a bucket of freshly brewed compost tea. Compost tea is essentially compost-brewed water that is aerated for 24 hours and mixed with a bit of molasses (or other sugar). Compost tea takes the beneficial bacteria and fungus present in compost increases them exponentially by aeration and sugars. These bacteria and fungus are critical in root establishment. Soaking your new plant in compost tea literally loads the root ball with beneficial soil microorganisms right before it gets planted. More on compost tea later.

Next time you plant, have a bucket of rainwater or compost tea by your side. I promise, you’ll notice a difference.

Native Combinations: 2 for the Shade

noreply@blogger.com (Thomas) — Thu, 19 May 2011 09:30:00 +0000

Solidago flexicaulis (Zigzag Solidago) blooms on the side of the road in Vermont. Image by Thomas Rainer

A shade tolerant Solidago? A few years ago, I saw a beautiful clump of Solidago flexicaulis (Zigzag Goldenrod) on the side of the road in Vermont. It was so stunning I stopped the car and pulled out the camera (my wife loves it when I do this—our vacation pictures have more plants in them than people). Initially, I could not identify the flower. The plant’s broad-leaves have sharply serrated edges. That foliage combined with the glowing-yellow racemes reminded me immediately of the ornamental perennial, Ligulara ‘The Rocket’. Was this some kind of native Ligularia I did not know?

Sharply serrated leaves of Zigzag Goldenrod

This plant really stumped me, mostly because I never assumed Goldenrods could handle as much shade as this plant was in. But after about 200 Google searches, I finally discovered that this was indeed a native Goldenrod. Solidago flexicaulis loves moist soil on the edge of a woodland—in this condition it masses spectacularly. But it is also highly tolerant of dry shade in high light conditions. It tends not to mass as strongly in dry shade, but it still looks great. The plant’s broad-leaved foliage looks great in a shade garden. The plant can easily be grown by seed and spreads rhizomatically.

Want to use Zigzag Goldenrod in combination with other shade tolerant natives? In the same area I discovered the Solidago, Aster cordifolius (Heart-Leaved Aster) was in full bloom. The Heart-Leaved Aster is the same height as the Goldenrod, and the sky-blue daisies of the aster combined with the jasmine-yellow Goldenrod create a sparkling ground plane. The cultivars ‘Avondale’ and ‘Little Carlow’ are nice selections of this species. For best results, plant this combination along the edge of a lawn in an area of the garden that is shady, but gets high light. Neither species looks its best in dense shade. Because the aster grows together in a dense tangle of foliage, don't interplant them one by one. Instead, clump them in pockets of 3-5 plants side by side for the most legible results.

Unlike most shade perennials, both this Solidago and Aster bloom in late summer and early fall, providing interest during a time of year when most shade gardens are just foliage. Pollinators—particularly long and short tongued bees, wasps, flies, and butterflies—love both species. Remember, these insects are a vital source of food to many woodland songbirds. Aster divaricatus (White Wood Aster) would be another great native to mix in combination with these plants.

To Dig or Not to Dig: Are 'No-Dig' Planting Methods for Real?

noreply@blogger.com (Thomas) — Mon, 16 May 2011 09:00:00 +0000

photo by Jim Richardson, National Geographic

One recent garden trend that is spreading with inexorable speed is the “no-dig” or “no-till” method of planting. The basic idea is that plants are installed directly into the ground without tilling or turning over the soil. While this method is centuries old, it challenges conventional gardening practices of tilling and breaking in the soil before one plants.

I’ve been aware of this method for a while, but have been surprised by how quickly it has become dogma, particularly within sustainable landscape circles. When teaching a class on soil preparation, I mentioned tilling and watched as many of the students recoiled in protest. “Isn’t tilling bad?” one student immediately asked. I was taken aback. ‘No-dig’ is not just an idea, but a doctrine, a creed, a badge of one’s eco-credentials. Proponents spread the message with revolutionary fervor.

So is it time to put your tiller on Craigslist? Let me weigh in on this complex issue and hopefully provide some clarity. The gardening world has more than its fair share of old wives tales and superstitions. This is particularly true with anything regarding soil. We understand so little about what goes on in the soil, yet we dig, till, fertilize, and amend it with reckless zeal. When it comes to soil cultivation, what’s true?

Here’s the bottom line: ‘no-dig’ is great, but not when the soil is severely compacted.

After going through quite a bit of research, the evidence certainly favors the ‘no-dig’ approach. Part of me really wanted to find flaws with this method; after all, breaking the soil before planting just feels so natural, so downright human. Egyptian paintings 1200 years bc show people plowing fields. But the evidence generally supports the wisdom of not digging. Why?

Soil is the weathered mantle of the earth. It is not really even a solid, but a mix of mineral solids (45%), organic matter (5%), and water and air (25%). In its undisturbed state, soil is generally layered with the top few inches containing organic matter, the next few inches containing topsoil (soil that is mixed with organic matter), below that subsoil (generally denser and less organic), below that decomposed rock, and below that rock. This basic structure is vitally important to plants, as this layering creates large pores (macropores) through which air and water move. In addition, soil’s layered horizons create a living network of bacteria, fungus, molds, and other critters that symbiotically support plant growth. Plant roots move through soil pores, following the air and water. Plants grow their roots by connecting their root hairs onto mycorrhizal webs in the soil. These fungi supply plants with nutrients and water while in return, they obtain sugars from the plant through photosynthesis. At least 95% of plants are known to use mycorrhizal webs.

Mycorrhizae attach to roots

Tilling and digging disrupt this vital soil network. When you sink a shovel in the ground and flip the soil over, you break the mycorrhizal network. When you till, you may be breaking the soil into fine enough particles that it compacts even more, obliterating many of the necessary pores in the soil. In fact, studies have shown that plants grown without tilling initially outperform plants grown in tilled soil. At a larger scale, no-tillage agriculture has been proven to reduce erosion, increase crop yields, and decrease greenhouse gasses.

So should you get rid of that tiller? Not just yet. While the ‘no-dig’ method is generally a good way to plant, it does not work well in heavily compacted soils. Compacted soils are common in human-disturbed landscapes. Soils can get compacted enough that air and water no longer move through it. Soils compacted to this level are deadly to plants. If you plan to plant in heavily compacted soils, some method of decompaction—subsoiling, tilling, or aeration—is absolutely necessary. Think throwing organic matter on top is good enough? No way. The problem with severe compaction is that it never goes away. If air and water can’t move through it, it will not cure itself.

How can you tell if your soil is compacted enough to justify decompaction? One of the simplest tools is a hand-held penetrometer. This device has a rod that gets shoved into the ground and measures the resistance in pounds per square inch. A small dial on the top will let you know what psi the soil is. Generally anything above 250 psi should be decompacted. Penetrometers cost a few hundred bucks, so they’re definitely worthwhile for a large site, or if you evaluate a lot of sites (all you landscape architects out there—get one for your firm). But penetrometer are crude tools and vary somewhat depending on the velocity you shove it in the ground. Other ways of measuring soil compaction is through Proctor test. Generally anything above 85% proctor will inhibit root growth.

Photo by William Cullina shows the effects of organic matter on post construction site. The soil on the left received no organic matter.
The soil in the middle had organic matter added only to the top few inches. The soil on the right had organic matter incorporated
throughout.

Don’t want to bother with complicated compaction equipment? The simplest way to test for compaction is to shove a pointed rod or stick into the ground. If it can easily penetrate the ground to a depth of 8-12”, your soil is probably fine. If it can’t, you may need to consider some method of decompaction.

The bottom line is that ‘no-dig’ and ‘no-till’ methods are great for relatively healthy soils. But if you have a site in an urban area, or one that is under construction, expect compacted soils. The best way to address deep compaction is to use some kind of subsoiling equipment. Tillers breaks up soil into fine particles that ultimately compact more densely. Subsoilers rip the earth--like a knife going through butter--in vertical lines that preserve the soil structure, while at the same time allowing air and water to pass through hardpan. Subsoiling equipment is typically attached to a tractor, but in smaller sites any kind of trencher (like an irrigation trencher) will have the same effect. Subsoil in lines 18-24" apart in both directions. When subsoiling, check for underground utililties prior to ripping the soil.

If you plan to address compaction by adding organic matter, one must add enough organic matter (or topsoil, sand, peat moss) to make a difference. Don’t just sprinkle some compost in the planting hole—this does almost nothing. Organic amendments must be mixed to a depth of 18 inches minimally and enough added to reach 25 percent by volume in sandy loam or 50 percent by volume in clay in order to make a positive change in bulk density and macroporosity. Decompacting soils is expensive and labor intensive, but worth it in the long run.

But if you have relatively healthy garden soil free of compaction, try a ‘no-dig’ approach. It’s actually much easier, and you will be surprised by the results.

The New Azalea Garden at The New York Botanical Garden

noreply@blogger.com (Thomas) — Wed, 11 May 2011 09:00:00 +0000

photo by Angel Franco/The New York Times

This week The New York Times wrote a glowing review of the newly renovated Azalea Garden at The New York Botanical Garden. I worked on the design for that garden while at Oehme, van Sweden and Associates.
The assignment was one of the most complex planting projects I’ve worked on. The New York Botanical Garden was in the process of redesigning the eleven-acre azalea gardens in house, but they hired OvS to design a complete palette of herbaceous plantings to compliment the sprawling shrub garden.

The challenge was to provide seasonal spectacle throughout the year, not just around Mother’s Day when the garden attracts thousands of visitors. Designing a perennial garden with year-round spectacle is hard enough; but doing it in deep shade and underneath and around 3,500 azaleas was an especially daunting task. How do you plant around, under, and next to so many azaleas? And how do you use perennials to blend and soften the jarring bubble-gum pinks, corals, oranges, and fuchsias of the azaleas?

We worked closely with the talented staff of The New York Botanical Garden who was designing the layout of the azaleas. If you are a landscape architect, making recommendations to a botanical garden like NYBG is like a computer programmer making recommendations to Bill Gates or Steve Jobs. The Garden’s staff—led by Todd Forrest and executed by Jessica Arcate Schuler, Deanna Curtis, Kristin Schleiter, and Travis Beck—has some of the most knowledgeable plantsmen in the country.

photo by Angel Franco/The New York Times

The site itself ultimately provided the solution. The Azalea Garden is located on eleven acres of rolling forest, complete with massive hardwoods, granite outcroppings, and stunning vistas. The OvS concept divided the garden into seven character zones and matched herbaceous plantings to these zones. Perennials along the perimeter road, for example, were massed in larger groupings so they could be seen from the trolley; perennials along the dark entry walk featured brightly-colored foliage and more intricate blooms visible at a pedestrian scale. The site’s highest point used grasses and wildflowers to evoke the feeling of being in a high elevation bald.

The strength of these evocative character rooms was praised by the Times:
Nothing could be more artificial, yet it will eventually seem to have almost casually evolved out of the natural landscape, presenting a microcosm of the world’s azaleas and rhododendrons that just happened to display themselves for our pleasure, shifting character with season and age. This is a garden designed to display the suitability of plants to place, while demonstrating the inexorable passage of time — and that may be the most natural phenomenon of all.

I left OvS before the construction of this Garden. So did Ching-Fang Chen who inspired much of the early concept and added systematic rigor to our detailed plantings. Principal Sheila Brady and project manager and designer Hilary Oat-Judge saw the project through construction. Ultimately, however, it is NYBG who edited, designed, purchased, and laid out the herbaceous plantings. The craft and skill of their staff created one of the most inspired and interesting Azalea Gardens in the world.

RadioGarden: The Best Garden Podcast Period

noreply@blogger.com (Thomas) — Wed, 20 Apr 2011 19:39:00 +0000

If you haven't checked out Andrew Key's RadioGarden, my friend, you are missing out. Andrew Keys wears many hats in the gardening world: designer, writer, entrepreneur, and blogger. Andrew has made gardening hip for the iPod generation. I had already been following his witty blog Garden Smackdown, when I saw that he was starting a radio podcast for Horticulture Magazine.

This peaked my interest. For years, I've been searching for a GOOD garden podcast to pass the time while I do my studio work. But it's slim pickings in the garden podcast world. The vast majority of them are overly polite how-to's (today's episode: how to prune hydrangeas); or call in shows where every other caller wants to know what they can plant that will withstand dog pee. Mind numbing stuff.

RadioGarden is a breath of fresh air. In an era where garden media is dominated by "garden celebrities" like P. Allen Smith (trademark!) and corporate sponsorships from Scotts/Miracle-Gro, Andrew Keys is the antidote. Fresh, witty, and real, Andrew tells stories about the intersection of plants and people. Inspired by Ira Glass' This American Life, Andrew's show exposes the real connections between people and the gardens they love. There's no pretension here. Just good, raw storytelling told with a journalist's eye for detail and a poet's sensibility.

Andrew has produced four quality episodes so far. The only question is: can Andrew keep it up with all his other commitments and interests? I certainly hope so. It's time for this show to go big time.

You can listen yourself right here on Horticulture Magazine's website. Or download the podcasts from iTunes.

Grounded Design is One Year Old

noreply@blogger.com (Thomas) — Fri, 15 Apr 2011 09:15:00 +0000

Grounded Design is celebrating its one year anniversary this month. Aren't blog years like dog years? One blog year feels like at least seven human years. Of course, so many of my favorite bloggers have been doing great posts for multiple years, like Susan Harris whose been blogging since 2005. Now that's inspiring (I'm a bit of a late adopter myself . . . oooh, iPods?!).

I had meager expectations when starting this blog. I thought I'd give my wife a break from my rants about gardens, landscapes, and planting and direct these ramblings into a blog site. I expected only my parents and perhaps a few other friends I guilted into signing up for emails to read this. I still remember the joy of getting my very first comment on the blog (even if it was an angry complaint from a company in the UK named Grounded Design).

The most rewarding part about blogging is you. I still can't believe anyone reads this, and I never expected such thoughtful, creative, and diverse group of readers. All I can say is thank you. Thank you for reading, for commenting, and for all your great work in your own blogs. You make this worthwhile and a joy.