Viagrow Vermiculite is a natural soil amendment that promotes moisture retention and aeration in potting mixes and delivers vital elements to the plant roots resulting in better root development, growth rates and yields. Viagrow vermiculite can be mixed with Peat moss, mushroom compost, cactus soil, organic soil, bark, perlite, compost, coconut coir, worm casting, potting soil and just about any soil or soilless media. Viagrow Vermiculite number 3 naturally attracts and holds positively charged ions, like potassium, magnesium, calcium and ammonium, releasing these vital elements to the plant roots. It even contains potassium and magnesium, which are then available as a supplemental slow-release supply of essential nutrients. Vermiculite is great for container gardens, square foot gardening, raised bed gardens, green house mixes and hydroponic drip systems.