Comments for The Japanese Maple Guide

Comment on Japanese maple questions and answers – 3 by Tony Hobbs

Tony Hobbs — Fri, 20 Nov 2009 22:24:19 +0000

Very interesting, not what I expected at all, there was me thinking they needed shade, misconception! Mine is in shade, I planted it from pot (leaves kept getting burnt in full sun) to a shady spot in the corner – ops! It has only been there for a year it is quite small, can it be transplanted to full sun near my pond?
Do the roots get quite big and are they a danger to structures like ponds and foundation / drainage / sewers?

Comment on Should a Japanese maple be grown in shade? by Tony Hobbs

Tony Hobbs — Fri, 20 Nov 2009 22:05:03 +0000

I planted a Japanese maple in a sheltered spot in the garden, it survived last winters freezing cold weather. It is in the shade of 2 other small trees, but can’t remember the names of the trees, but one well known the other less so.
The maples leaves do get a bit crispy during the summer, even in the shaded position, anything to help prevent that?
When I had it in the full sun the leaves were even worse!
Also, is there a difference between acer and maple?
PS – not read full article yet!!!

Comment on Japanese maple questions and answers – 4a by florist

florist — Wed, 18 Nov 2009 14:56:32 +0000

It was nice going through it. keep it up the good work.
–thanks–

Comment on Aphid damage to a Japanese maple by Flowers

Flowers — Sun, 01 Nov 2009 05:07:47 +0000

Thanks for sharing the info as I was unaware of the fact that aphid damage to a Japanese maple occurs in spring. Your article was quite helpful as I have grown aphids in my garden.

Comment on Japanese maple questions and answers – 4 by Helen at Toronto Gardens

Helen at Toronto Gardens — Tue, 20 Oct 2009 21:44:29 +0000

Great advice. It’s amazing how many plants are killed by “too much love.” Overwatering is often the number one danger to any potted plant.

Comment on Pruning a Japanese maple – don’t try this at home by John

John — Thu, 08 Oct 2009 18:45:33 +0000

The reason given for pruning the tree in the summer was because the client wanted it done. A properly trained arboriculturalist would have a duty to advise the client of the negative consequences of pruning at that time of year, not only for Japanese maples but all trees and shrubs.

Presumably Dr. Shigo didn’t elaborate on the phrase ‘right after the leaves emerge’, but in practice this would be once initial growth had stopped and shoots had started to lignify. Major sap flow would have ceased and little or no bleeding would occur. The drawback, however, is you deprive the plant of the ability to build up food reserves; after all, that’s what the leaves are designed to do! We are then left with one perfect time of year, just after leaf fall.

The reference to pruning at any time of the year (excluding the period of heavy sap flow) is, strictly speaking, correct but, as you point out, would be limited to very light pruning and specifically only the pinching out of shoot tips to control growth.

Comment on Pruning a Japanese maple – don’t try this at home by M. D. Vaden - Portland Landscape & Trees

M. D. Vaden - Portland Landscape & Trees — Thu, 08 Oct 2009 15:26:34 +0000

What I find a bit odd with the video – potentially – is maybe how much was pruned-away in one session in summer.

Dr. Alex Shigo the Father of modern arboriculture, wrote in a tree biology book that the optimum time of year would occur twice a year, right after the leaves emerge, and right after the leaves drop off. A so called generic “perfect” time of year. Within two pages though, he mentioned that pruning can be done “any” time of year. And the context would not mean heavy pruning.

The cold months do seem to be a prime season though.

Cheers,

MDV
Oregon

Comment on Should a Japanese maple be grown in shade? by John

John — Mon, 28 Sep 2009 17:32:55 +0000

With an appropriate mulch for a dry climate in place, no rain for two months won’t have any damaging effect. Quite by chance, I grew some seedlings for two and a half years without any natural or man-made irrigation and they happily survived. Although maples never lack rain in the wild, it is constancy rather than quantity that is essential when growing them outside their natural habitat.

You provide a clue in your description of your irrigation method. I assume you are using a conventional mulch such as bark chippings or compost – this is behaving as a sponge and obviously no water is going to penetrate into the soil with the result that most of the feeding roots are going to be in the mulch. The depth of the water table is largely immaterial as there is always going to be moisture in the soil, albeit in quantities we can’t measure by sight or feel, and your maples are able to utilise that when they’re trained to do so.

The inter-related subjects of mulching and watering are of some importance, particularly when grown on the margins of their ‘comfort zone’ such as your Mediterranean climate and I will be covering them in more detail shortly.

Comment on Should a Japanese maple be grown in shade? by Augustin Coello

Augustin Coello — Fri, 25 Sep 2009 20:36:58 +0000

“with an effective mulch in place watering should not be necessary”
Not when you do not get any rain for more than two months as has happened here this summer, if they are not watered they would die. These maples like a short (15′) sprinkling from a drip irrigation system each day to keep the mulch humid. Underneath, the clay is dry to the bone (my water table is 25 meters deep). Do not forget that in their natural range, as you say, they never lack water for long periods. The Mediterranean climate is clearly not very good for Japanese maples.

Comment on Should a Japanese maple be grown in shade? by John

John — Wed, 23 Sep 2009 18:42:08 +0000

From my experience with variegated cultivars, and in conversations with commercial growers in Australia, New Zealand and USA using open ground production, generally they will tolerate full sun with no ill effect. With their reduction in chlorophyll due to the variegation, their need for as much sun as possible compared to plain leaved forms is probably greater.

As far as humidity is concerned, this can make a crucial difference between success and failure (or at least burnt leaves) in a hot climate. With the highest temperatures in Japan coinciding with the highest rainfall, humidity is assured but with dry air, transpiration losses are going to be such that a less than perfect root system is not going to be able to cope. I notice you mention appropriate watering and mulching together – with an effective mulch in place watering should not be necessary and would serve only to confuse the root system by artificially manipulating the water table. Allowing the roots to find a natural water source under the mulch over the course of a season should help to mitigate any damage as constant lack of irrigated water tends to produce a reduction in growth rather than burnt leaves.

Do you find the same problem with dwarf and dissectum forms? Logic would dictate that with a dense canopy of leaves, these types would provide greater shading of the soil and probably a more beneficial micro-climate.