Grodan 1m vital slab

Grodan stonewool (rockwool) was developed in Denmark in the early 1970's.The process makes excellent use of nature resources; We can produce 37 cu.ft. of wool from 1 cu. Ft. of rocks.
Today most Grodan is pro-duced from recycled Grodan.
Grodan stonewool is the main reason that most of the worlds greenhouse vegetables are now grown hydroponically.
At full saturation, Grodan holds 80-90% of its volume in water. It is wrapped in biodegradable plastic and the stonewool can be re-used in your garden to improve the aeration and water holding capacity.
Grodan stonewool went into space on Challenger in 1986 and is still being used in NASA's testing with hydroponics.
You will also find Grodan products at the EPCOT center / Walt Disney in Florida
You will find Grodan stonewool in some garden centres and in virtually all hydroponics shops around the world.