Grodan 36x36x40 mm planting cubes with hole and planter 77 pcs. Rockwool Grodan is a high-quality, inert medium that provides the conditions for profitable cultivation of plants and crops. The culture substrate made of basalt wool has excellent absorption properties and ensures a balanced water/air ratio, which promotes root development. The hole size is 6x15 mm, and the size of the planter with cubes is 53x32x4.5 cm.