Coast of Maine Organic Products Sprout Island Organic Seed Starter is a rich mixture of blended sphagnum peat moss, perlite, kelp meal, worm castings and well-aged compost. It contains mycorrhizae and is ready to use in cell packs* or flats and provides natural moisture retention and aeration. It has a mild organic fertilizer charge that creates a biologically diverse environment ideal for germinating seeds and root cuttings.