Grodan Rockwool is a mineral wool made from molten basalt and limestone rock that is spun into cotton-candy like fibres and then compressed into cubes, blocks or slabs. Being made from natural rock, Grodan is a mineral based product used in hydroponic growing applications.
SBS 36/77 propagation grow cubes are a small starter cube ideal for seeds and cuttings which will fit easily into the small hole in each cube. Each cube measures 1.5 x 1.5 x 1.5 inches (3.6 x 3.6 x 4cm approx.) and this product is presented in a black draining tray containing 77 cubes per tray.
The grow cubes guide the root growth downwards.