Are you growing a deciduous bonsai? Is it a coniferous bonsai? Is it a tropical or sub-tropical bonsai?
Fertilizing your Bonsai is a main resource in aiding in the growth and preservation of it.
Soil type and composition
Choosing the right soil and its composition is vital for the health of your Bonsai tree.
The tree root system is a bit more complex than the one of flowers and herbs.
For early germination some peat soil and dirt can be sufficient, but once the tree grows big it will need some new mixtures to get stronger and keep healthy.
A mixture of peat moss, sand and soil is the way the tree would normally grow in nature. Add peat moss and nutrients to your soil when needed to ensure your roots grow healthy, but make sure you keep pruning the roots as needed to keep the bonsai tree in its shape and size.
The fertilizer is not for the plant but for the soil in which the plant is planted in. It holds nutrients such as potassium, minerals, nitrogen and phosphorous that keeps the soil that the tree grows in as a healthy environment. When the fertilizer is working it will release the nutrients in it to the soil in a way that the bonsai tree roots are able to absorb them best.
Time to fertilize
It is recommended to feed the Bonsai tree with fertilizer on a weekly basis during the growing season (Early spring till late summer). As the tree gets older and the growth slows, it’s recommended to reduce feeding to once a month.
Different kinds of trees require minor alternations for ideal fertilizing, so if you want to get the best results check on the specific type of the tree that you are growing and the recommended fertilizer to use and best way to use it.
When not to fertilize your Bonsai tree
One time to not add fertilizers to your tree’s soil is when it looks sick and weak. You’d probably think that it is when it needs it most, to become strong and healthy again, but this is the time when it needs different ways of caring like managing moisture levels in the soil and pruning weak roots.
Other times that you should hold on fertilizing your plants are when the soil is too dry, first bring the moisture back.
During dormancy is another time to not fertilize the soil and let the tree keep growing in fertilizer free soil.
After repotting your plant you should also hold and not fertilize it for some time until it gets familiar to its new surrounding and settles in. You should wait to see that transplanting it didn’t give it too much stress and that it keeps growing healthy.