What qualities does the potting media need to have?

[gbarce]

I know that the general rule is the media need to be low in nutrients but what other qualities does in need to have.

Here in the Philippines I've seen them sold in heavy clay soil and a moss/coconut fiber which have very very differing qualities.

[alcran]

Depending on the humidity and frequency of watering the media can differ in density and water retention. A very heavy media like pure sphagnum or clay are used in dry and hot places where waterings need to be frequent. Light mixes with higher amounts of aggerates like coco fiber and bark are used in enviroments where humidity is high and waterings frequent.