As water is the main food of the bonsaï, the beauty and health of the plant depends on the quality of watering. Here’s some advice :
As water is the main element of the nutrition of the tree, you must be very careful to water it properly. Bear in mind that if you water it too much it will die, and if you water it too little it will die as well !
In fact, the roots of a bonsaï are very fragile. Too much water will cause them to rot. Too little will dry them out. Rather than following the technical notice indicating the frequency of watering, you should water according to your observations of the needs of the plant. This is a tricky balance to achieve, as generally a clod of soil kept humid all year round will not give the desired effect : roots constantly fept humid soil will rot.
It is therefore necessary to install a draining substratum. Compost should never be used as it has the disadvantage of drying out very quickly and thus becomes impermeable. On the other hand, it may also retain too much humidity, and therefore rot the roots. Never forget that is always easier to save a tree which lacks water than to save one which has been watered too much.
The best type of substratum is a mixture of akadama, pozzolana, pumice and rough sand. Avoid at all costs the “special bonsaï” composts available in the shops as they are entirely unsuitable for gowing bonsaï !
Traditionally, watering is carried out every day in restrricted quantities. The technique consists of watering the plant from above with a very fine shower of water. The water should run over the leaves to wash them and to get rid of pests (mainly acarids). If you use with tap water, allow it to settle it a few hours before watering in order to eliminate the chlorine.
Another technique is used in the case af severe dehydration. This consists of plunging the pot in a basin a water until the water reaches the level of the outer rim of the pot. When the water rises naturally in the pot, take the bonsaï out and drain off the water.
Important : Bearing in mind that a bonsaï needs to be watered everyday, if you go off on holidays make sure to leave it with someone who knows how to water it. If you dion’t know anybody, bring the plant with you. If it isn’t watered for several days in the summer, it will be dead when you get back !