75x75x65mm Stonewool 8pk - Planting Propagation Growing Assist Block NutrifieldNutrifield Stonewool is a reliable and beneficial substrate for gardeners. It contains a low density and vertically oriented fibre structure, this allows for simple irrigation and drainage which optimises root development. These substrates provide root development protection and control, that assist in generating the highest quality crop. Features: Control and Flexibility Nutrifields Stonewool substrate is essential for unrestricted and uniform root