Wonder Soil Wonder Soil Expanding Nutrient Cube - Makes 2.5 Cubic Feet Well-balanced blend that includes humus, worm castings, water storing polymers and mycorrhizae A pH level of 6.5, and will feed plants up to 4 months (no need to fertilize for six months) Makes 2.5 cubic feet of potting mix - 11 planting blocks will make 1 cubic yard Expands up to 7 times its volume when hydrated, in just minutes Does not contain weed seeds, fungus, or gnats