The object of this section of the Bonsai Primer is to cover those areas not dealt with in the section on pests and diseases and to help you recover (hopefully) a sick tree.
A lot of potential problems can be averted with a few precautions,
these I would suggest are:
Here in the UK we get a lot of trees imported from China, trees of variable quality and size. These trees are potted up in any old soil available, usually a fine clay. This compacts down and in a very short time will choke the tree. Most responsible Bonsai importers repot the tree into an open compost at the first opportunity and so should you.
Should your tree keel over, the best thing you can do is to enclose it in a clear plastic bag and keep it in the semi-shade, It should pull through. Water it with a fungicide and a systemic insecticide before you do. Don't rush to repot it this can do more harm than good.
Whatever you do don't feed it until it has recovered.
I receive a lot of e-mail, from people who are worried that their tree is unwell, as "some of the leaves are turning yellow and dropping off". You should remember that leaves have a finite life span, this is of course one year with deciduous trees, several on evergreens and five or more with conifers, when they reach the end of that span they turn yellow and drop off (as do we all), This process is called Abscission.
If however all the leaves die, then there is a problem and you will need to think carefully about what caused it. In my experience this tends to be a problem caused by a lack of light with trees kept indoors, or overwatering.
With outdoor trees, total leaf loss, outside if the normal season, usually indicates the death of the tree.
© Allen. C. Roffey 22:06 16/06/2005