A JBP with a root ball of pure clay

(Bruce Williams) #1

Last year I acquired a very healthy JBP at a nursery sale. The tree is about 40 inches high, very full and obviously had not had anything done to it since it was dug. It survived our winter in great shape and it was only a week ago I began to clean it up and to think in terms of re-potting.
To my horror, I discovered the 24 inch root ball is still wrapped in burlap inside the container and the soil, if I dare call it that, is pure clay. It’s scary, hard as a rock and water seems to run right off it.
So, if I do attempt a re-pot, how, what, where and when??? I suspect if I start on this root ball with a chopstick, I may spend the entire summer just removing 50% of the soil.
I’m near Seattle in 8a.

(Frank Corrigan) #2

The good news is the tree is healthy at this point. The bad news is this will take time to fix. My approach would involve a series of repots.
First time, remove as much soil as possible from the to and locate the nebari, then move to the bottom and remove the old soil in the center directly under the trunk as much as possible. I would then comb out the edge around the perimeter to expose healthy roots and remove dead roots. Amount to be determined by root condition, stopping when mostly healthy roots have been exposed.
I would anticipate reducing the rootball by 1/3 on the overall size and having excavated most of the central core.
I would then change repot techniques to 1/2 HBR on the next two successive repots. This should result in the entire removal of old soil within three sessions. Say this spring, next fall and the following spring as the plan for timing.
Oh, and i should have mentioned that i would downsize the pot or grow box for a tighter fit as i progressed to reduce the root ball and prepare for a proper sized bonsai pot.
Perhaps others will have additional insight or alternative approaches to consider.

(Bruce Williams) #3

Thanks Frank, as you can guess I want to be very careful with this tree. Unlike much nursery stock, it has some great trunk movement. I suspect this is the reason it didn’t sell last year.
I know the quickest way to set it back or kill it will be when I work on the roots.
I will take it slow and work mostly on the bottom in the middle. Hope I can post some pics when I get it out of the nursery pot…

(Raymond Mack) #4

Could it be too late for this operation, depending on your location? The buds on my pines here in zone 7A have started extending. According to my experience and advice of my teacher it’s too late for me. But if you’re in a colder zone it may be the perfect time. Not giving advice just sharing the way I operate. I know there are many ways to skin our green cats.

Best regards to all,