Caring for a bonsai tree (or any plant for that matter) is like caring for a pet or a child. To grow a healthy bonsai tree, you will need to ensure that it receives all the nutrients and care it needs. Like all organisms, bonsai trees are susceptible to diseases and pests. If not detected in time, these ailments can prove to be fatal for the tree.
Here is a quick guide the symptoms that you should look out for on your bonsai tree.
The overall look of the bonsai is a good indicator as to the state of health of the plant. Except during the winter months, the tree should have lush and thick foliages all year round. Excessive shedding of leaves and bare branches may be signs of a disease or improper environmental conditions (lack of sunlight, nutrients etc).
If the tree suddenly looses its foliage (usually over two or three days), it may be caused by frost, poison or dehydration. Dehydration is thus far the most common cause of sudden leave sheds. Where the soil in the pot is dry, the leaves of the bonsai tree would die within hours.
There are some types of trees (such as some elms, and Firethorns) that will suddenly shed it s leaves to make way for the growth of new leaves. There is nothing much to worry about if you find buds of fresh leaves growing at the spots where the old leaves once were.
The growth rate of your plant is also another good indicator of health for your bonsai tree. Tree varieties such as the Trident maple are very fast growing while the Boxwood and Chinese Juniper are generally slow growing trees. Depending on the type of tree that you are planting, a normal growing pattern is a sign of a healthy tree. Stunted and incredibly slow growth rates may be signs of stress or infection.
Pests and infections usually cause gradual decline in the healthy of your bonsai. Black flies, caterpillars and snails cause physical damage to the bonsai by eating the leaves, and soft tips of the tree. Although such pests usually do not cause fatal damages, they can kill the tree if left unchecked over time. Regular doses of insecticides will easily keep such pests under control.
Viruses and fungi are by far the greatest treat to bonsai plants. An infected plant can easily spread the disease to other bonsais, causing a health epidemic in your garden. A plant that is affected by viruses or fungi will display a stunted and distorted growth. This is usually accompanied by discoloration and abnormal patches on the plant.
When infected by fungi (such as mildew and rust), the infected part of the plants should be removed immediately to avoid further infection. The use of fungicide is also helpful in preventing and treating fungus infections.