What is the best soil for bonsai trees?

Bonsai soil mixture available in Canada


The right soil mixture is one of the most crucial factors in the health of your trees. Bonsai soil should provide enough drainage to prevent the roots from rotting, while also helping to absorb enough water for the tree.

Important features of a high quality bonsai soil:

  • Has water-retention properties that supplies moisture to your bonsai tree between each watering
  • Allows excess water to drain quickly from the pot which prevents water salt build up 
  • Provides excellent aeration which allows oxygen to reach the roots of the bonsai tree

At The Bonsai Tool & Supply Company of Canada, our handcrafted specialty blend of bonsai soil has been tailored and refined over a decade of time and tested with our own trees. Our unique bonsai soil consists of:

Red and black lava rock

Lava rock makes an excellent substrate as it retains water but doesn't all bonsai tree roots to grow into it. Lava rock is solidified molten igneous rock that has flowed from volcanic eruptions.


Haydite makes an excellent addition to bonsai soil substrate as it is a unique, lightweight aggregate prepared by expanding select minerals (such as shale, clay and slate) in a rotary kiln at temperatures over 2200°F.

 Conifer bark 

Conifer bark is an organic material that contributes nutrients to the bonsai soil and also functions as a storage place for moisture.

 Visit our shop's bonsai soil section for more information.

What to avoid in bonsai soil:

  • Never use regular potting soil as bonsai trees require regular drainage and potting soil does not dry out at a quick enough rate to allow for this
  • Bonsai soil that is exclusively made up of aquarium gravel or similar gravel products as they have no moisture or nutrient holding capacity

Do you have any questions about bonsai soil? We're the experts! Feel free to send us a note and we'll get back to you as soon as we can.