Bonsai Care - How to Water

By Paul March

Do you water a bonsai like any other plant? Of course not. Lots of factors affect bonsai including climate and environment and there are very specific ways on how they should be treated.

Bonsai use water at different rates, which means that because there are many different types of bonsai they will all use water at different times and amounts during their growing cycle. All bonsai are not the same. Different species of bonsai do not have set cycles and should be tended to when necessary.

Watering - be careful never to let the compost dry out. By allowing compost to dry, you can quickly kill a bonsai tree. When trees and plants are in their natural environment they quickly adapt to the conditions of the soil - this is not possible with bonsai as because of the small scale, whatever you do - or not - has a fast effect on it. It is said in Japan that to master the proper watering of a bonsai it takes 3 years.

Under-watering will do more harm to your bonsai than over-watering. Take a careful note of the compost and be careful not to let it dry out.

Remember that in order to breathe the roots of a bonsai need oxygen - oxygen is provided when water comes into contact with the roots and all the by products are flushed out and exchanges fresh air which nourishes the plant. Too much water and you will suffocate the plant - where there is too much oxygen, the fine root hairs cannot breathe.

How do you know what the right amount of water is? Sometimes if you are re-potting you can tell that a plant is over-watered because the fine root hairs will turn black and rotten.

Some of the signs which may indicate that you are not watering correctly are - the smaller branches shrink and die away - foliage turns yellow - the plant suffers a lack of vigor and looks tired not healthy.

So what can be done to remedy this? Cutting away the black roots will help. Rotten roots foster bacteria that kill the plant, so cutting the old rotten black roots away will help restore a more friendly eco system and help the plant to recover. Take care not to damage the healthy roots as this will impede recovery. More importantly you will need to change your watering habits!

How often do you water? Never on a set routine. Temperature changes and changing environment mean that you need to adapt to what your bonsai needs. Bonsai only have a small root system and can dry out very quickly, you must keep a careful eye on the needs of each individual plant. Your plant may have damp compost on top, but below be drying out. Each species bonsai plant will use water at different rates according to their living conditions, and must be checked daily.

A tip to help you find out what is going on beneath the surface is to put a wooden toothpick into the soil and leave it there. When you check next the toothpick will help you to see if the compost below the surface has dried out, by looking at the lack of dampness and this will help you assess how much water you need to use.

You need to be able to adapt your routine to the needs of your plant and never underestimate how important watering is.