Section 14562 Of Article 2. Definitions From California Food And Agricultural Code >> Division 7. >> Chapter 5. >> Article 2.

. "Soilless growing medium" means a medium of an inorganic substance, such as sand or gravel, or in a soilless organic material such as sphagnum peat or pine bark, and periodically watered with a primary or secondary plant nutrient or micronutrient solution, or both.