repotting question - root bound Shimpakus

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ADO
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repotting question - root bound Shimpakus

Post by ADO »

Hi guys :wave:

I have two Juniper Shimpaku in normal plastic nursery pots. I think they are around 7 years old at sale and I bought them a few weeks ago. I think they have been in their pots for a long time and haven't been repotted for sometime. The soil is pretty mucky and organic and its doesn't drain too well. I know I must repot these trees into larger training pots with a coarse mostly inorganic mix - the question is, how do I deal with the roots and soil?

from research, it seems that bare rooting a juniper is a big no-no but I have read some advice to the contrary. the beauty about bare rooting is that I can get the roots in amongst good soil straight away. but i don't want to kill the trees.
as an alternative, maybe I could keep some soil, trim a few of the old roots and then put in good mix?

any help appreciated!
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Re: repotting question - root bound Shimpakus

Post by GavinG »

Hmm. How precious are they, and how bad is the soil?

I've bare-rooted junipers a couple of times, just at bud burst, and put them in 100% very coarse sand or pumice. Your equivalent might be the Carnarvon gravel. Mist the leaves, keep in shade a couple of weeks. Only do it if you feel you have no alternative, it's risky.

Otherwise gently, gently. Get what you can of the compacted nasty stuff directly under the trunk, and leave the outside roots relatively undisturbed, this time.

Best of luck,

Gavin
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Re: repotting question - root bound Shimpakus

Post by ADO »

Hi Gavin

thanks for the reply, :yes:

the soil is very black and peaty. the roots basically conform to the shape of the pot. basically when I water, the water pools at the top of the pot and takes some time to run through the pot.
they are nice trees and have healthy foliage at the moment. but i would not cry (much) if they died in the name of repotting.

so in terms of taking things gently, can i untangle some of the roots that are bound?? I feel if I don't do this it will be hard for the tree to make new roots or for a new mix to make a difference?
will the tree be able to grow if I dont untangle the roots and just sort out the mess under the rootball?
sorry for all the questions - its my first season repotting Juniper (Ficus are so easy!)

cheers :yes:

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Re: repotting question - root bound Shimpakus

Post by Guy »

(if it were mine)--I would remove from pot and saw off 1/3 rootball ---use a sharp knife and vertically slice the out side surface of rootball every inch or so---if the plant is very healthy I would also dig up through the centre of the rootball and cut the main centre roots and(so as to not disturb the remaining roots) leave them there-fillup centrewith good mix then repot in slightly larger pot--and seasol soak--part shade for a couple of months
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Re: repotting question - root bound Shimpakus

Post by kcpoole »

Reduce the root all depth and then tease out the roots from the side of the root mass without disturbing too many if you can and not cutting them much if you can avoid it.

Repot and work you mix into the teased out roots leaving the rest undisturbed.
Next years work you can then take sections out of the old root mass to start getting out the gunky soil.

After the root work, Seasol drinks for at least a few months until you see good positive growth.

Ken
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Re: repotting question - root bound Shimpakus

Post by ADO »

Thanks gentlemen.

I just repotted one leaving most of the roots intact and cleaning out the gunky soil from underneath the root ball. then I wired into an oversize training pot, watered with seasol and ill leave it in the shade for a while.
I assume that I should leave off wiring, pruning etc until it recovers?
cheers again :tu:
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