As I have discussed in a few previous post, there are really no secret recipes for bonsai soil mix. The subject itself has been one of controversy for a long time. However, if we start with the basics the task of choose the ‘right’ soil or mixing it ‘right’ can be a lot less daunting.
It is important to remember that to the tree in the pot, its soil is its greatest concern. If your existence depended as much on soil mixture you would be concerned to. So getting right down to the basics there are only two requirements for good soil:
- Moisture Retention
- Nutrition Dispersion
The moisture retaining requirements will vary throughout the range of specie. To keep it simple, this is what I have done for years and if you want you can call it my ‘secret’ recipe. I’ve known a few Bonsai Masters that claim to have their own ‘secret’ recipe, although they are always willing to share it with anyone. So much for the ‘secret’ recipes!
So really all I do is starting with a mix of 50:50 Grit and Water Retaining material. Some swear by using organic material for water retention but I believe that is just a preference and how you feel about the environment. With no more soil than is required for a bonsai, I can see no environmental impact one way or the other..
IMPORTANT: The one thing that you should never do to your bonsai; never use regular compost or garden soil. It will hold too much water and will cause the dreadful ‘Root Rot.’ You may spread some collected moss over the surface, which will often have a small amount of regular soil. The moss will help minimize evaporation, thus keeping the roots moist until next watering.
Rather than giving up a big spew about using this and that, what I have done is a little research and found a great article written by a well-known Bonsai Master, whom I had the opportunity to meet during my years with the Greater Evansville Bonsai Society (although he don’t like to be called ‘Master’) I would like to share with you his “Thoughts on Bonsai Soil”, published by the Ann Arbor Bonsai Society of Ann Arbor, Michigan. See link at the bottom of this post.
If you keep in mind the two main requirements, that I mentioned earlier, you will have no problems raising a vigorous, beautiful bonsai.