Using the right bonsai soil mix can be very beneficial for a bonsai tree. There are a lot of enthusiasts who use ready-mix bonsai soil from nurseries and garden shops but it is quite expensive. Because of frequent re-potting during spring, most bonsai hobbyists or gardeners learn mixing soils on their own.
There is a wide variety of soil ingredients to use. For starters, choosing which type of soil to use can be very difficult. It is important that the bonsai soil can hold moisture and nutrients needed by the plant because the health and beauty of the bonsai tree heavily depends on the quality of soil.
The soil should have good hold of water but excess water should also be drained quickly to avoid build up of salts. Good air intake of the soil is also vital. The soil mix should have small-sized gaps so that the roots can have enough air. A well-mixed inorganic soil allows air to continually flow into the soil while a packed down organic soil can hinder water and air flow that can cause damage to the roots.
An organic bonsai soil is comprised of dead plant substances like peat, dead leaves and barks. An inorganic bonsai soil is composed of fired clays and volcanic lava. This type of soil can be found in garden centers and nurseries.
Although most bonsai plants require soils good for water retention and draining excess water, there are species that have their own requirements for intake of nutrients and water. For example, Pine trees and Juniper trees need lesser water intake meaning they require less-water-retention type of soil. However, flowering and fruit-bearing species require soil mixes with high level of water retention.
When mixing your own bonsai potting soil, the percentage of water-holding material should depend on the specie of the tree that will be planted. For a free-draining soil, high ration of grit should be added making the soil drain all excess water while increasing the quantity of water-holding material, which also increases the retention of water in the soil.
Proper knowledge on what soil to use is very essential for a healthy and beautiful bonsai tree. It is fine for starters to use a ready-mixed bonsai soil from a nursery or garden center for the first few times. However, the use of inorganic soil is the most recommended.
