This the best media for growing healthy plant from seedlings, the offer is for a pack of 5 cubes 4 in.x 4 in. x 4 in. each, rapid drain (the channels on the bottom).The world of hydroponics has discover rockwool and its special properties suited for growing plants, it retains moisture and air in the right ratio to keep your plants growing and growing without the stress of too much or too little water. GOOD STUFF.New, in its clear packaging
DID YOU KNOW:To make rockwool, manufacturers use combination of chalk and rock and then heat it up to around 3,000 degrees Fahrenheit. Next a stream of air is blown through it (the molten rock), resulting in extremely thin fibers of the rocky material. As the strings are blown out, they bunch together and form the material that you see for sale at the local hydroponics store.

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