Harris Vermiculite Helps with soil aeration and drainage to keep your plants looking healthy. The Premium Horticultural Vermiculite is pH neutral, non-flammable, odorless, non toxic, and will not decay or shrink. Use with cuttings, bulbs, soil, composted bark and more. Listed with the Organic Minerals Research Institute for organic use.Harris Succulent and Cactus Potting Soil Mix is designed to provide the best possible drainage and stability for all your succulents and various cacti. As a balanced blend of premium quality Forest Humus, Pumice, Compost, Perlite, Sphagnum Peat Moss, Fish Bone Meal and Limestone, it boasts both excellent drainage and water holding capabilities. It is great for both indoor and outdoor cacti, succulents, and all drought tolerant plants. Because most succulents are slow growing, the key to healthy and optimal growth is well-drained soil.