Growool has a unique combination of properties which make it an excellent growing medium. These properties need to be considered if the material is to be used to its maximum effectiveness.

Properties:

• Very light when dry, with a void space of 95%

• Natural rock and is not biodegradable

• Sterile when packed

• Inorganic and contains no nutrients 

• Very low cation exchange capacity, so will not bind nutrients

• A slight pH rise on initial wetting, after which it has no influence on pH and nutrient solution it contains 

• High water and air holding capacity, typically 70% water and 25% air. 

• The aeration of this media can be influenced by the height of the Growool and how tightly it has been packed into the container.