Calibonsai Horticultural Lava

While this lava rock is excellent for drainage and aeration, it is best used as a component in a custom soil mix rather than a standalone medium. Most bonsai enthusiasts blend it with organic materials like pine bark or akadama to balance moisture retention with the drainage benefits this rock provides.

No, the color is natural to the volcanic rock and will not fade or bleed. It is a stable, inorganic material that maintains its appearance even after repeated watering.

It is highly recommended to rinse the lava rock before use. While it is horticultural-grade, the bag may contain fine dust particles from shipping and handling that can clog drainage holes if not washed away.

The grain size ranges from 1/16 inch to 1/2 inch, which is versatile enough for most container sizes. If you are working with very small starter pots, you may find a few pieces on the larger end of that spectrum that you'll want to set aside or use for larger arrangements.

Unlike perlite, which is lightweight and tends to float to the surface of your soil over time, this volcanic lava rock is dense and heavy. It stays put in your soil mix, providing a more stable foundation for plants that need to be anchored securely, such as bonsai.

Absolutely. While it is formulated for cacti and bonsai, it works well as a top dressing for any houseplant that prefers a drier surface or needs extra stability. It helps prevent soil compaction and keeps the top layer of soil tidy.