The 4”x4”x3” block from GROW!T Commercial Coco is designed for the vegetative stage. These small blocks fit easily into grow trays to help maximize plant counts in the early stages of growth. RapidRIZE blocks start off compressed for easy shipping and storage, but they expand fully in approximately 1 minute after saturation. All RapidRIZE blocks feature a wide, low-profile shape, to match the specific rooting pattern of your favorite herbaceous annual plants.