The hydroponic growing media of choice! Grodan Rockwool or stonewool is made from molten rock spun into cotton candy-like fibers and then compressed into cubes, blocks or slabs. Rockwool’s superb quality, fiber structure and pathogen-free content enables optimal root development for unrivaled growth and production.
Grodan has the highest density on the market, which translates into the greatest structural integrity for increased and longer oxygen holding capabilities. Low density rockwool collapses with the weight from water and plants, squeezing out air pockets and decreasing oxygen retention. High density gives better insulation value — especially important during germination and rooting of cuttings. Higher density also improves the wicking and dispersion of moisture and nutrients, enticing roots into more areas of the medium, and therefore increasing nutrient fueled sites for premium plant production.
Expert Slabs (6″ W x 36″ L x 3″ T, wrapped) are recommended for larger crops with extensive roots like peppers and tomatoes. Typically, seedlings in blocks are placed onto slabs.