What Is Vermiculite?
Vermiculite is the geological name of a group of materials containing aluminium-iron magnesium silicates. It resembles mica in appearance. Horticultural grade vermiculite is produced by exposing the raw materials to a flame at a temperature of 1000°C. The material is sterilized at this temperature and also expands, producing air gaps between the material. These air gaps allow a rapid uptake of moisture, and also a rapid delivery of moisture to plants roots. Even when saturated, vermiculite maintains tiny pockets of air which is a perfect environment for a plant roots to flourish. Water held in vermiculite is not easily removed and so a plants roots actually grow into the tiny gaps within the medium.
An interesting fact about vermiculite is that it will take up ammonia and is therefore can be useful in grows where a build up ammonia could be a problem.
Advantages Of Vermiculite
- Clean to handle
- Non abrasive
- High water holding capacity
- High water delivering capacity
- Even distribution of nutrients to a plants roots
- Stimulates root growth
- Sterile growing medium without pests, disease or seed contamination
- Can be stored without deterioration indefinitely (when dry)