If you’re new to growing Bonsai trees, chances are you bought yours from a big box store, a market, or a plant nursery. But trees from these places often come planted in a garden or potting soil, which is not an ideal substrate to facilitate vigorous bonsai growth. However, Bonsai trees require special soil considerations if you want them to grow well. The quality of the bonsai soil you use has a direct effect on the health and vigour of the tree. If your tree is planted in normal or poor garden soil (which easily hardens when it gets dry), the bonsai will not benefit in any way. There is a good chance it may even be harmed. 


Soil vs Substrate

There is no hard and fast rule when it comes to the type of soil to use to grow bonsai, as every hobbyist tends to have their own recipe mix for their trees. The situation is very much individual opinion, in a way that one person’s soil composition for tropical trees may be too light or too heavy for another’s tree. Some might argue that many bonsai mixes may not even be soil at all, given that it doesn’t actually contain any soil — not in the traditional sense at least. Many refer to their bonsai substrate as “mixes” to avoid the confusion.
Ultimately, regardless of what you use for any tree, the real difference between traditional soil and bonsai mix is that drainage is optimal. 


What to look for in Bonsai Substrate

If you want to maintain the health of your tree and facilitate vigorous growth, here are some of the things you need to look for in bonsai soil or substrate:

 1. Great water retention

First things first, the substrate should be able to hold and retain sufficient quantities of water. That way, it can supply moisture to the bonsai tree between each watering.

2. Excellent drainage

Perhaps the most important quality of all, the soil must have good drainage in order to work for your tree. Excess water must be able to drain immediately from the pot. Soils that lack good drainage retain too much water, lack aeration, and are liable to a buildup of salts – all of which are detrimental to the health of the tree.
Additionally, soil that is too water retentive will also cause the roots to rot, killing the tree.

3. Good aeration

The particles used in a bonsai mix should also be of sufficient size to allow air pockets between each particle.
In addition to needing oxygen for the roots, it’s also vital to let the good bacteria and mycorrhizae stay intact. This way the processing of nutrients will take place before being absorbed by the root hairs, before then being sent to the leaves for photosynthesis.
A particle-based, well-structured, inorganic soil usually allows for fast drainage of water and lets in fresh air continually to the soil. Meanwhile, a compacted organic soil without structure lacks aeration and drainage, leading to a negative effect on the health of the roots and tree.   

In conclusion

If you want your bonsai tree to grow well, then you need to procure a great bonsai soil mix. The right mix will inform you of the condition of the tree and let you know when it needs water. On the other hand, a bad mix will only result in a delayed growth and deterioration of health.

Should you need bonsai soil that will help you grow your tree, or if you want to start growing bonsai – we are here for you!We offer bonsai starter kits in Australia, as well as bonsai pots, bonsai tools, and bonsai accessories!