Better Than Rocks will make your planters lighter and promote better drainage and superior plant health in containers of all shapes and sizes. Not only will you enjoy more beautiful and healthier plants, you can say goodbye to rocks, aluminum cans, packing peanuts, and broken clay pot shards! Made of 100% recycled plastic and safe for both floral and edible plants, Better Than Rocks is the smart, eco-friendly solution for container gardens and can be re-used year after year. The Better Than Rocks 8" x 8" (20 cm x 20 cm) Twin Pack is perfect for eight inch containers. Each non-woven plastic mesh square is 1.5” thick and can be used in either square or round containers with no additional cutting. For a round plant container, fold the corners up or down and alternate each layer. The material is very flexible, so there is no need to trim the squares into circles, although you certainly have that option.