Grodan Stonewool (rockwool) is made from molten rock spun into cotton candy-like fibers and then compressed into cubes, blocks, or slabs. Where other rockwool brand manufacturers cut all sizes from one batch of wool, Grodan is unique by making different types of fibers. The purpose is to support the requirement of the plant in the different plant stages. Grodan has a tremendous capacity for absorbing nutrient solution while retaining plenty of oxygen for rapid plant growth. Grodan comes in graduated sizes. Seedlings started in cubes are easily transferred to blocks and then onto slabs, if desired. Seedlings or cuttings started in the Grodan cubes can also be transplanted into more traditional planters and growing mediums.
Gro-Slabs provide the final stage for growing a spectacularly large plant. Transplant your Gro-Block™ plant onto a slab just like professional growers. They come in clearly marked biodegradable UV resistant sleeves for comfortable handling and algae prevention. Uni-slab™ - All plant roots are protected and contained for the life of the plant. Due to its size, the Uni-Slab™ is perfect for one large plant. Uni-Slab ™has the benefits of a slab with the versatility of a block. All Gro-Slabs have vertical fibers except the 12 inch Gro-Slab, which has horizontal fibers.