Pruning a Maple?

[TheDarkHorseOne]

Howdy, folks. I have this Japanese Maple that I bought at a big box. At the time (July), it had leaves that were green and all of them were sun scorched on the edges. That compelled me to defoliate and the results have been excellent, budding all over the tree, but it's coming out with purplish leaves, and that worries me as I've read that you shouldn't defoliate a red Maple. It's come back, and I'm happy for that, but it brings me to the question, should I prune it in the Fall? I've also read that that's the right time for Maples, as if you do it in Spring, you'll have sap flowing at the wounds.

So, the question for me when is the right time to cut back (possibly wire), and should you do it to a red Maple that's been defoliated? It has really long shoots in spots and some excellent nebari for a big box tree. I'm also thinking of using the cuttings for propagation.

Experiences voices here would be most welcome.

 

[0soyoung]

Prune after leaf drop. It matters not what you've done to it the season before. The defoliation you've done means only that root growth has been retarded from what it might have been. In short order you will find that Japanese Maple branches are quite brittle - you'll only be able to wire thin new shoots/twigs to direct next season's growth. Alternatively you can wire in the spring, but the wire will need to come off in a matter of weeks.

 

[Brian Van Fleet]

I prune/wire them in the dead of winter. It seems like the sap flow stays fairly active (here), even a month after leaf drop. Here is a J. Maple progression that shows the development of the tree over the course of 10 years or so. It covers everything from pruning, wiring, pinching, defoliating, and repotting:
http://www.nebaribonsai.com/Nebari_Bonsai_112109/Projects_files/Evolution of Jap Maple.pdf

Cuttings, spring/early summer. Probably too late for this year.

 

[MACH5]

There is an on going debate as to what is best time to prune maples. I believe a lot of it depends on your local climate and also the maple variety. I personally much prefer to prune late Winter into early Spring. I have not had much success, specially with thinner branches, pruning after leaf fall and has resulted in either the branch completely dying or dieback. Very rarely had I had any issues with the tree bleeding out and causing death to the branch in early Spring. I am also a huge proponent of covering all wounds with cut paste as I have noticed trees heal much faster when it is applied while also preventing excessive bleeding.

In short what has worked well for me in the North East is Autumn: ok to prune only big, thick branches. Spring: ok to prune from big to small branches. Good luck with your tree and have fun!


@Brian: Always love to see this progression. Beautiful work and very instructive!

 

[TheDarkHorseOne]

Here's a thought for you, folks. This tree was defoliated in mid-July. Now, what I want to use as cuttings would be all the vigorous excess that's growing out of the tops of two long shoots which I'll be pruning anyway. Wouldn't the tree consider these areas of growth as 'Spring' growth? Therefore, wouldn't that part of the tree essentially be in it's 'Spring', and therefore robust for cuttings? If length of time from now to first frost is the prohibitive factor here, there's always bringing them indoors and slowly acclimating them to the cold if they're developing roots, eh?

I'm not stating this, I'm asking. In the long run, if I cut back in the Fall, I'll essentially be just tossing the cut off parts anyway, so why not do it now and see if they live? Naught ventured, naught gained, eh? And at the very least, that part of the tree is going to be removed anyway. So, in talking myself into this, the last positive factor is that I'll learn about the tree, and I think removing the vigorous tufts now will promote buds further back on the tree to get invigorated.

 

[0soyoung]

TDHO,

Since the alternative is to simply toss the trimmings, why not give it a try and let us know how it works out?

However, I doubt that your cuttings will root AND survive the winter. My thinking is that a JM cutting can possibly grow roots anytime you've got leaves and those leaves are in a humid environment by misting or tenting (e.g., cover a pot with a plastic bag or the like) with speckled/shady sunlight. Rooting is likely to take more than three weeks. Then the roots must be able to sustain the cutting and to 'harden' before winter. This nascent tree also must store away enough starch before leaf-fall to be able to fire up next spring; else, you'll wind up dead sticks.

IMHO, it really has nothing to do with the mother tree 'thinking it is spring'. It is the biological work that must be done by the cutting to survive the winter - my guess is that when the 4th of July fireworks went off in Indy, it was very marginal if not too late.

 

[Brian Van Fleet]

Or...you could leave the tree alone, let the new growth pump up the whole tree, and wait until spring to strike cuttings...increasing the size of the stock, and increasing the likelihood of success with cuttings. Timing is everything in bonsai...figure that out and you can get away with almost anything.

 

[MACH5]

I agree with what has already been said above. Japanese maples are notoriously difficult to propagate via cuttings. Because of this I would at least wait until Spring to make your cuttings if you so desire. I suggest you consider air layering instead which by and large is a much more effective way to propagate your maple.

 

[TheDarkHorseOne]

I agree with what has already been said above. Japanese maples are notoriously difficult to propagate via cuttings. Because of this I would at least wait until Spring to make your cuttings if you so desire. I suggest you consider air layering instead which by and large is a much more effective way to propagate your maple.

Well, the ayes have it. No pruning back this year. Good advice. I think I was just letting that impatience bug go to work on me, heheh.

It's a BEAUTIFUL tree, and since the defoliation, it's come near all the way back with extraordinarily purple foliage which tinge back into green, it seems, when it gets more shade or matures. It's right outside my front window and what once was bare twigs is near filling the space between sill and blind with delicate, near lacy leaves. I'm so happy I bought her.

I wanted to quote your post specifically, MACH, because air layering came to my mind as well. You see, the tree has two near equal branches which start very low on the tree. Not a double trunk, but but a split tree more like. Hold your hand up and do a peace sign with your fingers pretty close together and that's what it looks like visually, with a slim trunk below that. I was thinking for a while that I could somehow push them apart and use one as a first branch, but it's just too thick, really. So one thought of mine was to air layer one of the branches and begin the process of maybe a 'weeping' moyogi? If I can thicken the trunk but not the two branches in question, it may do well as a shizen-zukuri and avoid the removal of one branch entirely?

I think I need to get a proper camera and actually show you folks what's going on, but in the mean, I hope my explanation was adequate.

 

[MACH5]

Dark Horse your explanation is well understood. Definitely try and post a pic of your maple so that you can get better suggestions in design possibilities. A pic is worth a thousand!