Here are some basic tips on how to care for bonsai from the Iowa Bonsai Association. Remember that each bonsai has its own set of needs and each species of bonsai is different.

Watering

One of the biggest causes of bonsai loss is improper watering. Most bonsai need to be watered every one to two days, but the watering also depends on the species, size of pot, humidity and the soil. The soil should not be soaking wet but not bone dry. 

Fertilizing

Water-soluble fertilizer should be applied every 2 to 4 weeks during growing season. Remember that you should not feed the plant right after repotting or if the bonsai is sick.

Repotting

Bonsai need to be repotted periodically with fresh soil. Most bonsai should be repotted about every 2 to 3 years.

Lighting

Indoor bonsai, typically, can not tolerate temperature below 40 to 50 degrees fahrenheit. They should be under grow lights about 12 hours per day. In the summer, bonsai can be placed outside in partial shade.