All About Akadama
What is Akadama?
Akadama is a naturally occurring mineral that is highly valued by bonsai enthusiasts around the world as a soil. Surface-mined from volcanic material in Japan, Akadama has been a favorite of local Japanese bonsai growers for centuries. Akadama, which translates from Japanese as “red ball earth” in English, gets its reddish color from oxidation, and has a clay-like, granular consistency.
As a highly porous soil, Akadama provides an excellent pot environment for bonsai, allowing excess water to flow through it easily. This helps to prevent root rot, which is a common problem for bonsai grown in soil that doesn't drain well. That being said, Akadama is also great at retaining water, ensuring that your bonsai won’t get too thirsty and dry.
In addition to excellent drainage, Akadama also provides good aeration for plant roots. The porous nature of the soil allows air to circulate through it, which helps keep bonsai roots healthy and promotes overall plant growth.
It’s important to note that while Akadama has a high ability to store nutrients, it does not provide nutrients itself. This is because there are no organic materials in Akadama bonsai soil. For this reason, it's important to fertilize when you use Akadama, so that your bonsai roots always have nutrients available to pull from. We like our Green Balance and Green Growth slow release pellets, but there are other good ones as well.
If you are looking to improve the health and growth of your bonsai trees, Akadama soil is definitely worth considering.
What size Akamada grain should I use for my bonsai?
For small trees, we recommend using our small grain shohin size Akadama. The smaller grain breaks down faster, thus supporting healthy root growth in smaller trees.
For larger, old specimen bonsai, we suggest using medium to large grain Akadama, although some people prefer to use small grain for larger trees as well.
There is some debate as to what each grain size of Akadama should be used for, including some who think that Akadama is just for looks. We are here to tell you that Akadama is far more valuable than just an aesthetic addition to your bonsai pot. Another real use of varied sizes of Akadama grain is for layering in your bonsai pot: you can use medium to large grain Akadama to improve drainage in the bottom of your bonsai pot, and small grain Akadama as a fine top layer. The larger grain Akadama will break down slower, so keep this in mind when choosing which grain size to use in your bonsai planting.
As for the type of Akadama you should use for bonsai, we suggest hard fired Akadama for all but the driest climates. Though Akadama is most commonly used with conifers, it works for other types of trees too.
What is the Best Bonsai Soil Mix?
Some people use Akadama straight while others have it as part of a mix. One of our favorites is the special “Professional Mix,” which contains Akadama, lava and pumice. You might hear it nicknamed "Boon Mix" after Boon Manakitivipart, a famous American bonsai artist and teacher. They are one and the same!
Our Professional Mix is ready to use right out of the bag. The soil particle sizes range from 1/16" - 1/4" which makes this soil mix suitable for almost all trees.
The main reason bonsai professionals love our Professional Mix is that it offers optimal drainage and water retention. This means that excess water drains quickly while optimal amounts for root absorption are held in the pores of the soil particles.
If your soil retains too much water, your roots may rot, which is another reason bonsai artists like our Professional mix. With just the right amount of drainage and water retention, this Akadama soil mix promotes excellent root growth. If you want to help your bonsai roots grow even more, you can use a Tie Pot.
How Do I Make Bonsai Soil Mix with Akadama?
We sell Boon’s Soil Mix premade and ready to go, but some people like to create their own soil mix. Here’s what you’ll need to make Boon’s Soil Mix, or Professional Soil Mix, as we call it:
⅓ hard Akadama
small amounts of Horticultural Charcoal to harbor beneficial bacteria and add humic acid
small amounts of Decomposed Granite to add weight and structure
Be careful not to add any organic components to your Akadama soil mix. Non-organic soil breaks down slowly, so you won’t have to repot as often. There will also be less (and potentially zero) clogging of the drain holes. Also, organic material can dry unevenly, creating wet pockets in the soil that will negatively affect your bonsai planting.