Grodan Stonewool (rockwool) is made from molten rock spun into cotton candy-like fibers and then compressed into cubes, blocks, or slabs. Grodan has a tremendous capacity for absorbing nutrient solution while retaining plenty of oxygen for rapid plant growth. Seedlings or cuttings started in the Grodan cubes can also be transplanted into more traditional planters and growing mediums.

Grodan Delta blocks are the most uniform blocks available on the market. They feature improved grooves at the base to promote better drainage. They are available in a large assortment of sizes and configurations to suit all types of plants.