AusBonsai

As mentioned in other threads such as viewtopic.php?f=131&t=12533&start=0 , I have 3 JBP that have grown as general nursery stock.

One is a bit yellow And I'm thinking of planting it out for a potential seed source.

This one is labelled Yatsubusa And I'm thinking of doing some air layers, or leaving it for now as it has cones developing, and although I have been advised that they may not be viable while the tree is in a pot, I thought it might be worth a go.

And then there is this one which has good low branches that have needles half the size of the top. I had also considered air layering the top for more trees.

However I have some issues to sort out. All are quite pot bound and none have been trained as bonsai stock. So my questions if anyone can help are as follows.....

1. How should I go about root pruning so I can repot? Other pot bound nursery stock I have done which has been all Natives I slice down the sides to get rid of the roots on the edge of the root ball, cut 1/2 the bottom off, rake out the middle of the under side, cut back into the tap root and any deformed roots in the middle, then rake out what's left and remove any deformed or overly large roots. I have had good success with this method. Will this work with a JBP?

2. If I do root prune, will I need to remove the tops? I would like to leave them for air layering, but not if that will mean I might lose the whole tree.

3. If I have to remove the tops to root prune, can I do the air layers and wait to do the repot later? Will the trees stay in good health if they are so pot bound?

The best quitde for Working JBB is to never cut the bottom and the top in the same year
Root prune 1 year, Trunk and brach work tghe next.

For me I will sort out roots first because if you spen lots of effort on the top without have a good root mass to support it then you can waste a lot of enrgy and effort. If I did the top and then killed the tree sorting the roots out later, then I would be quite pised off

Cut the bottom of the root mass off 1/3) then tease out the surface roots and side roots. Spread them out well in a wider shallower pot ( orchid pot)
Try not to disturb the entire root mass in 1 year. One side one year and then the other next.

Take it slow then sort the top.

Ken

Thanks Ken.

Does this still apply when the top is so long and lanky. The tall trees stand about 1m tall.

Amd if so, can I still put on an airlayer just after a root prune?

I repot pines almost the same as other trees and for developing JBPs I cut both roots and branches in the same year and have not had any problems doing so.

Dansai, be careful when doing this -

cut 1/2 the bottom off

. Some commercial growers put the small plant in the bottom of a pot then dump in potting mix. This means all the roots are in the bottom of the pot so cutting through the root mass like this can accidentally cut through the main stem leaving no roots. Fortunalely most species will produce new roots from the trunk when it is buried like this but some do not. I usually scrape down from the top until I can see good roots coming from the trunk before deciding where to cut through the rootball so I know it is safe.

If you want to leave most of the top on these and repot then cut off a small section of the base, slice down the sides in a few spots to sever any circling roots then try to open out the rootball. Then you can decide how much to cut off to get it in the new pot (assuming it will go in a larger pot to allow it to grow well for layering??) I have found pines to be far more forgiving than their reputation would have us believe.

Thanks Shibui,

I think I will do as you suggested with minimal root disturbance and place in larger pots.

shibui wrote: I have found pines to be far more forgiving than their reputation would have us believe.

I must admit, I have been a bit scared to jump in to these as I mainly grow natives and have few could be called actually bonsai. Pines seem a bit mysterious to me at the moment, but perhaps it's due to lack of experience. I have been growing Native Rainforest trees for the last 4 years and only recently got into Bonsai. There seems to be a lot of info out there on JBP, some of which is conflicting, but I have had trouble finding any that relates how to go about turning a general nursery plant into a bonsai.

What I have done when not wanting to disturb the roots too much was planting it into a bigger container, when it shows signs of vigorousness I start to scrap out the top of the root ball first, not too much, but only till I can see some fresh roots.

Then cover it with fresh mix and possibly some dynamic lifter. I usually found new feeders develop. From thence on, I usually use strong wooden stick to poke holes through the root ball all the way down, so water can run to the inside of the root ball. This will help the next repot a bit. It will help air to come through too. It is a slow and tedious process, but it will help the tree a little.