Made from molten lava that’s whipped like cotton candy, rockwool is chemically and biologically inert, making it the perfect media to grow your best crops free of external contamination or influence. The most popular size rockwool cube, these 4 x 4 x 4 inch Growing Blocks have 1-1/2 inch holes in the top to accept small cubes that hold germinated seeds or rooted clones for ‘blocking on’, giving them a bigger space to send out new roots. Growing blocks are great for ebb and flow hydroponic systems or for use as mid stage for plants. Blocks are individually wrapped in plastic on four sides to hold moisture and stop algae growth. The base of each block is grooved for complete drainage.
DM 10 Strip of 6 Cubes 4" x 4" x 4" (with hole)