The tree should have healthy foliage and a good root system. Banksia Bonsai trees grow well in a well-draining soil mix that is slightly acidic. You can create your own soil mix by combining equal ...

Bonsai trees require a special type of soil that is well-draining but still retains moisture. You can make your own bonsai soil mix by combining equal parts of akadama, pumice, and lava rock.