La laine de roche (aussi appelée rockwool) est un substrat de culture inerte fabriqué en faisant fondre de la roche basaltique et en la filant en fibres. Elle retient simultanément eau et air, ce qui en fait l'un des substrats les plus utilisés en hydroponique commerciale et en propagation.
Faits clés
- Inert, pH-neutral substrate — holds no nutrients, so growers have full control
- Excellent water-to-air ratio: retains moisture while maintaining 15–20% air porosity
- Available as propagation cubes (for seed starting and cloning), grow slabs, and granules
- Must be pre-soaked and pH-adjusted to 5.5–6.0 before use
- Non-biodegradable — requires specialist disposal; some operations recycle it
- Compatible with NFT, drip, and top-feed hydroponic systems