New 48-Pack - Plant Starter Grow Cubes 6" Blocks - Stone Wool - Rock Wool - Planting Cubes Each blcok 6?x6? x6? with 1.5" Center hole. 6" x 6" x 6" Rockwool Grow Blocks Cubes is perfect for hydroponic gardening. Made from stone wool, these cubes provide exceptional drainage and aeration for healthy plant growth. The cubes come in a convenient cube form and are ideal for use in a variety of hydroponic systems. The brand of these cubes are designed specifically for hydroponic gardening. These cubes are perfect for those who want to grow plants indoors or in small spaces. 48pc per ctn. SOAKING - Saturate the -Blocks with pH 7-8 water when starting cuttings. - When transplanting, use the same strength nutrient solution to soak the new media as you were feeding the plant - If submerging the blocks to saturate, keep them submerged in the solution until bubbling stops. IRRIGATION - If using a drip irrigation system, use one drip stake per grow bock, Irrigate as needed to keep the block moist but not saturated. - If using an ebb and flow system, irrigate when the block is approximately half its fully saturated weight. - If hand watering, keep the block moist but not fully saturated. - Do not to over saturate the block after the initial soak as this can slow plant growth