This is the single most important factor in the care of bonsai. Most bonsai die from a lack of water. A few die from too much of water. Your watering technique should be, pouring water slowly near the base of the tree until the excess water flows out the bottom of the container. As a general rule, in spring and autumn water every second day. In summer water every day and in winter water every third day. The amount of water that your bonsai needs, is dependant on 5 factors.
1. The depth and volume of soil. Your bonsai is growing in a limited shallow amount of soil with a drainage hole. A pot of 6cm in height will dry out 4 times slower than a 3 cm pot and not double as one would expect.
2. The colour of your pot. The bonsai in a dark pot will heat up faster and cause more evaporation, as opposed to a light pot, which will have less heat retention and evaporation.
3. The ambient temperature and exposure to the elements of wind, heat and humidity. The tree transpires and combined with the effects evaporation through heat and wind, will rapidly dry out the soil. You must ensure that your bonsai soil is not allowed to dry out for more than 2 days without your knowledge.
4. The bonsai species. Some species are utterly dependant on over watering, such as swamp cypress. Others do not like water and over watering may lead to root rot, such as Baobab. The amount of water depends on the species and to help gauge the quantity of water required by the bonsai, you will need to understand the origin of the trees natural environment. 5. Soil water retention. Clay type soils with fine particles will retain moisture far better than stony soils mixes. You will need to understand what the moisture retention of soil that your bonsai is grown in.
:) Hint: Place a wooden toothpick or chopstick in the soil for 5 minutes to establish the moisture content of the soil. If the toothpick is dry, water the bonsai. If the toothpick is wet, there is enough water within the soil.
Firethorns on special @ R150ea