AusBonsai

Hi All,

I have quite a few junipers of various types and particularly with the procumbens nanas, they seem to just have an absolute mass of fine fibrous roots. When I am repotting a tree like this, how should I go about training it to the point where it has fewer thick roots showing a good nebari? Do I preselect some thin roots and then just not prune them, but prune all the others? Repeat this over a few repots to develop the selected roots? Help!

A good technique I have used on many species is combing the roots with a chopstick or similar at repotting time. Eventually they get better.

Hi Andrew

It is a problem on the Junipers like Procumbens, P. Nana and Squamata especially. Much like letting a branch grow to let it thicken we can do the same to the roots as well. A good place to start though when root pruning is to remove all, or as many as you can initially, of the roots growing directly under the trunk leaving only the lateral root layer around the trunk. This has the added advantage of creating a better buttress at the base of the tree as all the growing energy comes in from the sides only, and leaves only those more surface roots to thicken.

I remove all the roots underneath at the earliest time possible in the development of the tree, and it is these roots that are the first to be pruned off at every repot if they regrow. It all takes time on a Juniper.

Best Regards

Tony

tony bebb
can you apply this methode to any tree,cutting the central root out and just keeping the side roots,
i have got several english oaks and wondering if it would work, as they have a major tap root
and a few azalia,s aswell
dean

G'day Dean, that should be standard practice with all trees. When training seed raised stock its best to remove the downwards growing roots as early as possible. I prefer to raise plants from cuttings as they tend to throw out nice radial roots and no tap.
Craigw

thanks craigw i will leave oaks till winter but play with the rest cheers dean

Dean

What CraigW said mate.
I reccomend it should be a continued practice at repotting time as even cuting grown trees can develop downward growing roots that can become main roots over time and are best removed to develop a better buttress.

Tony

thanks guy's what you said i shall do the only problem is i didnt know i had to do something like that but now i do i will be doing it to all
my plants i have i got a chinese elm which is about 3 year old and it hasnt been done and i brought it in a nursery about 7 months ago
so thankyou for advice shall start on tree's as soon as possible
cheers dean

Hey Dean

Just remember you may not be able to take all the roots from underneath at once. The main thing is to leave enough for the tree to survive, but take as much as you safely can at once. It sometimes needs to be done over 2 or 3 root prunes. Safety first.

Tony

When pruning these roots, would it also be worth planting the tree in a very shallow pot (more shallow than a normal bonsai pot) to stop the roots from growing downwards?

Hi Sean

Not necessary but possible. If the tree is mature and needs no more major development this is possible, but if you still want to fatten the trunk or grow more branches I would not reccomend it as they need room to grow. Once removed these roots will not regrow much between repots and they are the first roots I remove at this time. Always make sure the tree has the room it needs.

Tony

thanks tony and everyone else who helped
it was something i didnt know had to be done, so yesterday i did my serissa and removed the middle root,
and placed a rock under it to give the roots that are there some spread and i also did it to 1 of my soa-to-me
azalia and gave them both a good pruneing at the same time so now i know i need to remove main centre root
for better neribri and root spread
cheers dean

Hi Dean I have seen a japanese article on root training palmatum maples, where there are photographs of some guys working the underside of a tree with a little hand held plane, this practice is to encourage the root base to fare out, when you are repotting your trees you should be able to touch the underside of the trunk easily.
Craigw