Perlite
Superheated volcanic silicous rock
Origin: Produced worldwide but now mostly in China.
How much: $45 3 cu. ft.)
Reusable: Yes
pH: Neutral
CEC: Low
AFP: High-medium
WHC: Medium
Pros: Lightweight, readily-available, great for rooting cuttings, inert, chemically stable.
Cons: Has no buffering qualities, leaches nutrient easily and tends to float when flooded
Irrigation: Manual top-feed, Drip, ebb/flow and aeroponics?Nutrient Requirements: Naturally Inert medium, suits most hydroponic nutrient solutions.
Usage notes: Perlite is available in many grades. 4-12mm is most common for horticulture. Perlite can be used alone or amended into coir, vermiculite, peat moss, or soil mixes to improve aeration/drainage. A 50/50 mix of perlite and vermiculite is ideal for rooting most cuttings."
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