Shop our selection of Grodan Rockwool Cubes and Grodan Slabs used for easily placing seeds for growing plants. Grodan Rockwool products are the ideal growing substrate for plant propagation and precision growing. Grodan Rockwool Cubes and Grodan Slabs allow you to plant your roots at the right depth for optimal growing.For all growing projects and applications, Grodan Rockwool Cubes and Grodan Slabs are easy to use and will help speed up the growing process for your plants. In addition to Rockwool products, HTG Supply also offers a wide variety of grow mediums, propagation accessories, and seed starting supplies in our online store! Enhance your growing today with HTG Supply!