Hello Chankry. Coco is a growing medium containing coir dust, derived from the processing of coconuts. Its got many benefits not least no pests or soil born diseases. Check out those forums!
I thought I might try some out doors next summer ( I`m in the UK), nosey neighbours concern me though!!
Ah, a natural inert substrate....nice! I would love to try indoor, but Im beginning to realize it is time consuming, plus its a sin no to take advantage of the outdoor conditions I have in Peru!