Ground Growing Multi Trunk Juniper

[Bonds Guy]

I acquired this Shimpaku Juniper last year and my goal at the time was to only free the roots for its transition into a pond basket but I got a little carried away and ended up doing a partial repot.



Unfortunately I didn’t take an after photo but the tree is healthy and doing well.

As you can see the nebari looks good so my goal now is to get this guy in the ground so it can start beefing up. Only issue is I don’t know much about shimpakus or junipers for that matter.

So my question to you guys is, is there anything I should know before placing this tree in the ground? And is there anything I should know about ground growing junipers? I should also note that I’ll be placing a wood board under the tree to continue the development of the nebari

One last thing, I was told that junipers should only be repotted when tips are growing. Is that true?

 

[Wires_Guy_wires]

is there anything I should know before placing this tree in the ground?

Not particularly. But it will grow faster and get fatter faster, so wire early and make bends hard.

And is there anything I should know about ground growing junipers?

See the above, and keep in mind they need less water in the ground.

I should also note that I’ll be placing a wood board under the tree to continue the development of the nebari

This only works well if the trunk base is close to the board. If there is enough room for normal growth, it will not benefit the nebari development at all: it will just grow like a normal juniper in the ground.

One last thing, I was told that junipers should only be repotted when tips are growing. Is that true?

It's the best time to do it just before those tips grow in my opinion. But I've done it at other times too and it never failed except during the hot parts of summer.

 

[Shibui]

How do you think a board under the roots will improve the nebari? Feel free to do so but no point in adding a board to this tree IMHO. It already has well developed surface roots so adding a board won't give you anything more.
My experience is that shimpaku juniper take quite some time to start growing when planted in the ground. They seem to stand still for the first year, a little growth in year 2. Year 3 and on is when I see most growth and therefore thickening of trunks. I've been allowing 5 years in the ground for the trees I grow here. Balance between some trunk thickening V time spent. Will be interested to see if your experience is similar or different. Also remember you'll probably need to allow at least another 5 years after that to develop branches and canopy.

Bear in mind that ground growing will not put bends in the trunks. I find the opposite in that trunks tend to end up even straighter than before as they thicken more inside bends. This applies to all species and is the reason experienced growers recommend making early bends more severe than planned. Allows for some of the bend to disappear as the trunk thickens.

Ground growing also does not make taper. Subsequent chops will do that so plan for places you can chop or make deadwood.

Junipers do not bud easily on bare wood so it's important to maintain some growing shoots or branches on the lower sections of trunks. These will eventually be the basis of the live branches and trunk for your bonsai.

Trees develop unpredictably when ground growing. Some sections may grow more than others so what you end up with may not be a larger, thicker version of what you have now. I've given up planning a style before ground growing. Just need to work with whatever you end up with.

Also agree that transplant time for juniper is quite wide. Late winter/early Spring, before growth is good. Most of spring growth is good. Late summer also appears to be OK. Autumn and winter can be OK, too, depending on how cold the winters get.

 

[Bonds Guy]

How do you think a board under the roots will improve the nebari? Feel free to do so but no point in adding a board to this tree IMHO. It already has well developed surface roots so adding a board won't give you anything more.

It would maintain that nebari and prevent downward growing roots.

My experience is that shimpaku juniper take quite some time to start growing when planted in the ground. They seem to stand still for the first year, a little growth in year 2. Year 3 and on is when I see most growth and therefore thickening of trunks. I've been allowing 5 years in the ground for the trees I grow here. Balance between some trunk thickening V time spent. Will be interested to see if your experience is similar or different.

Np. I’ll make note to update this thread next year.

Bear in mind that ground growing will not put bends in the trunks. I find the opposite in that trunks tend to end up even straighter than before as they thicken more inside bends. This applies to all species and is the reason experienced growers recommend making early bends more severe than planned. Allows for some of the bend to disappear as the trunk thickens.

Yes in a thread about my young dawn redwood I believe it was you who told me the kink it had in the trunk would gradually go away as the trunk thickens and sure enough it did. In fact, if I didn’t have old pictures I’d forget where it was. Since then I learned whenever I put a tree in the ground to really exaggerate the bends and twists. I’ll definitely will be putting bends in this tree before I plant it in the ground.

Ground growing also does not make taper. Subsequent chops will do that so plan for places you can chop or make deadwood.

Isn’t the point of ground growing to create the base of the tree? Thus no need to periodically cutback since it’s going to be hard chopped once the base is established or in the case of this tree, cutback to low shoot?

 

[Shibui]

It would maintain that nebari and prevent downward growing roots.

Why prevent down growing roots at this stage? The nebari is already well established. Those surface roots won't move now, no matter which roots grow in the soil. The existing roots just get thicker over the next few years. A board will not 'maintain' existing roots. They are already there and will stay put.
Any down growing roots can be pruned off when you dig the tree in a few years so I don't see any purpose in restricting their growth.
A board might make some sense if you want to add more horizontal roots between the current roots in the existing nebari but to do that you will need to bare root and prune a lot of roots to get the board right up close to the existing surface roots as already mentioned by @Wires_Guy_wires above.

Isn’t the point of ground growing to create the base of the tree? Thus no need to periodically cutback since it’s going to be hard chopped once the base is established or in the case of this tree, cutback to low shoot?

Correct. The only issue is, junipers don't bud well from bare trunk so you will need to monitor to make sure there ARE still low shoots with suitable close foliage to chop back to when the time comes. When growing in the ground, most trees tend to put all the effort into upper and outer growth, leaving bare inner branches. No problem with maples and others that can bud easily but you may need to prune occasionally to maintain shoots suitable to chop back to when developing junipers.

As always, my advice is opinion only but based on nearly 30 years of growing trees in ground for bonsai. Feel free to take it or leave it as you see fit.

 

[Bonds Guy]

Why prevent down growing roots at this stage?

Easier dig. I should have mentioned that I will not be planting it in the ground like this. I just wanted to give you guys an idea of what I’m working with. When I do plant in the ground, I’ll be placing the board directly under the tree. From what I remember, most of the roots aren’t stiff so I don’t think I’ll have to remove much.

The only issue is, junipers don't bud well from bare trunk so you will need to monitor to make sure there ARE still low shoots with suitable close foliage to chop back to when the time comes.

I hear ya. I’m basically thinking of this as growing a pine

As always, my advice is opinion only but based on nearly 30 years of growing trees in ground for bonsai.

And its very much appreciated