Repotting a Japanese Black Pine

Hi all!
Recently I was told by a fellow Bonsai owner that I should repot my Japanese Black pine into its permanent bonsai pot ASAP! I’ve currently got it in a small plastic pot (with drainage holes) which I keep it in outside. I was wondering if anyone could confirm that I need to transfer it to it’s permanent location now, or whether I should continue repotting it into slightly bigger pots each time until it’s big enough for it’s permanent pot? (These pictures were taken inside but I keep it in my porch outside)
Many thanks,

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Your JBP seedling will be a couple of decades away from what we would normally describe as a more permanent Bonsai pot. The normal course of events will be upsizing the container gradually as training progresses to a grow box or in ground growing! That being said it is very common for people to want to rush small trees into pots before it is developed for maintenance in a Bonsai pot. This is common practice for beginners and less experienced hobbyists.
The purpose of developing seedlings through a series of containers is to develop the tree as well as the proper form of root ball that will allow it to thrive in a Bonsai container long term. It is also more efficient, requiring less soil, less water and more effective use of space during its development. As long as the containers are changed when required the progress of the tree will not be adversely affected.
I change containers when the roots are taking up most of the available space in the container. I like to check the roots on young pines ( 1-5 yr) each year in the late winter/early spring. At that time I trim strong roots and consider if the size is still appropriate for that tree! If you note a lot of roots growing out the bottom of the container or the soil stops draining properly then check the roots.


Hi Emily, this is a great question. I completely agree with Frank.

Your JBP is little more than a seedling, if your transferred it to a pot now I doubt the root ball would even be big enough to secure to the pot.
By keeping this plant in nursery pots and slowly upgrading them means you can thicken the trunk and strengthen the roots which are very necessary for a healthy bonsai in the future.

You can still prune and even wire the bonsai in nursery pots while you’re developing it. You don’t need to have it in a pot for those things.

I have even bought bonsai from growers that came in pots and then put them back into nursery training pots to increase trunk size.

For me, the best lesson bonsai teaches is patience. It can be easy to want to speed ahead but patience is key.
If you feel like you want a few potted bonsai around (because who doesn’t) then go and buy a few more mature trees that can be potted.

Good luck


Hi Frank!

Thank you for your advice! You’ve been very helpful and informative and I greatly appreciate it!
Taking your advice I will continue using nursing pots until my bonsai considerably bigger! :blush:

Many thanks and stay safe,


Hi Jarren!

Thank you also for your advice, I appreciate the help a lot!

Many thanks and stay safe!


Hi there.

I recently bought a Jack Pine bonsai starter kit, and it finally germinated ( see photo attached)

So my question is as follows:

Should I keep it in the current container ( it has a drainage hole at the bottom) or should I plant it in a bigger pot for more root growth. ( I don’t see any roots on my seedling yet.) any advice would be appreciated.


I suggest you review the comments in the above thread. Your question is the same as the one beginning this thread!