Bonsai tree soil information… Make sure your tree is happy!


So, did you know that Bonsai tree soil and Bonsai soil additives will determine the health of your Bonsai's roots?

As a tree grows, it will take water and minerals from the soil. Much of this revolves around oxygen, which exists between the soil particles. The lesson here is keep your soil aerated!

soil

Soil is the main medium in which your tree will get it's air and water. For most plant matter basic soils are fine, but with beautiful Bonsai trees, a more thought out bonsai tree soil is required, and sometimes Bonsai soil additives.

Before reading on, be sure to read our bonsai care guide and our 'How To' guide!

Also, for specific soil needs, check out our tree guides, alphabetically arranged from A-N and O-Z!

Lets start with Akadama.

Akadama, otherwise known as 'red clay soil', is now widely available, is manufactured in Japan and is graded by particle size (fine, very fine and standard).

This Bonsai tree soil contains no organic matter and despite it's clay-based composition is quite granular. The granules retain their structure for years and are able to drain and hold sufficient water. This makes it an ideal Bonsai tree soil.

Akadama is best suited to conditions like those in Japan: high summer rainfall and moderate cold temperatures in winter. The type of soil prevents waterlogging and then freezing.

In areas where climate conditions vary from the above, things are added to the soil to allow for the difference.

In North America, Europe and Mediterranean countries, bark, grit, baked clay and pumice can be added to ensure a balance between moisture retention and drainage. You can mix different size grains to achieve a mix that is right for your climate.

As a guide:

• Smaller grain sizes hold moisture better.

• Smaller grain sizes should be used in climates where rainfall is lower.

• To achieve moderate grain size mixes, mix together varying grain sizes.

• Soil particles that are too fine will clog the roots and prevent drainage.

The perfect Bonsai tree soil does not exist. Each soil needs to be customised to meet the demands of the environment within which the Bonsai resides.


Rule of thumb

• Heavy rainfall = soil with good drainage

• Light rainfall = soil with moisture retention properties

• Small Bonsai = small, fine particles

• Large Bonsai = larger particles

PinesPines and Junipers benefit from dry conditions, requiring a soil with good drainage, while Bonsai fruit trees require a Bonsai tree soil with loam and organic matter.

To aid you in the process of sorting soil particle sizes, specialist Bonsai sieves are available.

grit

TIP! When buying soil from nurseries, even if packaged as Bonsai soil, ensure there is a grit or granular content. Without this you can expect your tree to suffer! If you can't find a good Bonsai tree soil, make your own, using Bonsai soil additives…. It further adds to the organic Bonsai experience!

Here is a basic Soil Mix Guide:

General Mix

• 30% Akadama, loam or fine-medium granular structure

• 30% Organic medium moss (bark, peat etc)

• 40% Drainage medium (sand, pumice, grit)



Deciduous Mix

• 40% Akadama, loam or fine-medium granular structure

• 30% Organic medium moss (bark, peat etc)

• 30% Drainage medium (sand, pumice, grit)



Flowering Mix

• 50% Akadama, loam or fine-medium granular structure

• 20% Organic medium moss (bark, peat etc)

• 30% Drainage medium (sand, pumice, grit)



Pine

• 20% Akadama, loam or fine-medium granular structure

• 30% Organic medium moss (bark, peat etc)

• 50% Drainage medium (sand, pumice, grit)



Juniper

• 20% Akadama, loam or fine-medium granular structure

• 20% Organic medium moss (bark, peat etc)

• 60% Drainage medium (sand, pumice, grit)



IMPORTANT NOTE
When using clay soil mixes, ensure regular repotting, around every 2-3 years. Clay mixes often lose their structure and waterlogging becomes a problem!


If you have experience in making Bonsai tree soil, or if you are for composing one for the first time, its handy to know about Mycorrhiza.

Mycorrhiza is the symbiotic relationship between the white, powdery fungus that clings to roots, and actually protects a tree's roots from pathogens, increasing moisture and ensuring efficient nutrient absorption.

When repotting or composing new soil mixes, it can be handy to keep some of this fungus or add some by introducing decaying matter, like rotting pine needles!

The use of moss and lichen on older trees can look amazing and can provide the tree with some organic material. Visit our friends at drought-smart-plants.com to learn about moss and lichen!





Instead of driving around looking for the right soils, why not buy online? Below is a list of food and soil products perfect for your bonsai!



Leave Bonsai Tree Soil and head back to Bonsai Care!