As with a house your Bonsai needs a good foundation. Anything you can do to improve the vigour and volume of you roots will be reflected in the visible part of the tree. A strong, healthy root structure is generally a by-product of, feeding and Repotting/Root pruning together with a good open compost.
The Roots, as they leave the trunk should be exposed. This gives the impression of a powerful tree anchored into the ground, rather than a stick poked into the ground. This root flare is called 'Nebari'.
As with the branches the roots should radiate away from the trunk like the spokes of a wheel.
The root structure should ideally be close to the tree, that is to say it should have lots of fine roots close to the tree, not twisting around the inside of the pot.
No root should cross another above surface level. any that do, should be removed.
Here we see a program to improve the roots on a bonsai. and get them closer to the trunk. (a) Is as the tree was aquired, perhaps as nursery stock, or by collecting. (b) Shows the tree at first repot. several of the major roots have been cut back and treated with hormone rooting powder,or gel. (c) Is the tree at the end of the year, this may take longer if a conifer, so watch out!. (d) shows the remaining roots cut, and treated, and (e) the final result, a good radial root structure, close to the tree.
If you should find yourself with a tree with an absence of root close to the trunk, or perhaps only a couple of large roots in poor positions, don't give up. If you read the section on layering you will see that it is possible to induce new roots close to the trunk, and indeed on the trunk should the tree be lacking in a particular area.
Perhaps you have an uneven root spread with one root much larger than the others this can be brought more into balance by pruning the strong root harder than its rivals,when repotting. Over time this will even out the roots.
Over a few years the root at the front (a) has been pruned harder than the others, causing them to become more equal in size
|When either purchasing a tree for conversion, or collecting a tree from the wild, you will find
the tree will have a major root going downward. This is called the taproot and must be
removed for the tree to fit into a shallow bonsai pot.
This process may need to be carried out over several repottings and can in the case of pines take quite a while to achieve. However if you read the section on layering you will be able to induce new roots above the place where you wish to cut the taproot.
You may, if you have removed a lot of root at one time, have to remove some of the foliage to 'balance' the tree.
Creating a balance between the roots and
When you repot your tree, try to create a balance between the volume of root and the amount of foliage present. This may mean reducing the foliage, but a tree that is 'out of balance' like the one in the middle may find it difficult to survive.
© Allen. C. Roffey 22:09 16/06/2005