AusBonsai

Hey guys . Will post some pics later today .
I have a Japanese maple in a styrofoan box for a few years currently in about 3 inches of soil with lots of gealthy roots.
Ice selected a pot for it this year ... i know they can handle a good root prune but how much is to much to handle .
The new pot will be about 1 inch of depth . ( to the rim )
Will that be to much 2/3 of the roots. Should I do this process over a couple of years and just knock off half this season ?
Cheers

Hi Dibly,

I root pruned a Japanese Maple last weekend and took off at least 2/3. I suspect I could've gone harder, but it was enough I thought. I don't know much about your climate/conditions/after-care etc.. and would think this may also play a factor in how much you prune, but I have attached a link to a root pruning video from Tien (Bonsai Sensation) that he put in another thread related to Tridents that may be of help. If you scroll further down his web page past the tridents there are 2 videos related to a Japanese Maple you might find helpful.
Putting up pics will probably help too, plus it's nice just to see stuff
Good luck with it, here's that link :

http://bonsaisensation.com.au/how-to-prune/

2/3 should be fine to take off without too much concern

Ken

Thanks guys .
Good info ... When you say you did yours last weekend ryceman , is it pushing out buds yet ?
The maple is just showing signs and my elms are .
Toowoomba has a good climate for maples as far as im aware .
Should i wait till its covered in buds and just about to shoot out or rip into it now ?

I am going to tackle a couple I have now, they're still in nursery pots so will need to be more of a chop, have no idea what the roots look like. Will post couple pics when I do.

There was a recent discussion which spoke of Japanese maples bleeding when pruned once buds burst or start to push, so would think now would be good. Need to watch after care and reduce watering while tree recovers (don't dry I out). See what others say.

Have you considered reducing the height of the tree? Would personally look at reducing height to branch right middle and letting it grow for a season or two for taper. The pot would then also be more in proportion to height of trunk, roughly 2/3.

You can root prune JM for a few weeks before they start to bud so now will be a good time. I've been repotting some of mine in the last couple of weeks.
You should be able to remove more than 3/4 of the roots on your JM. I think it will go straight into the new pot. Just be aware that these shallow pots dry out very quickly on hot summer days and Jm do not like to get too dry. Your tree is relatively small for the new pot so it should be Ok as long as you water properly.

dibly_w wrote:Thanks guys .
Good info ... When you say you did yours last weekend ryceman , is it pushing out buds yet ?
The maple is just showing signs and my elms are .
Toowoomba has a good climate for maples as far as im aware .
Should i wait till its covered in buds and just about to shoot out or rip into it now ?

Buds are beginning to swell on mine and my elms have pushed out already on quite a few, for me I reckon it is the time to get the roots sorted, I agree with Shibui... go for it!