Size comparison of various diatomaceous earth soil amendment products
Almost everyone in the United States has heard of Kitty Litter®, a high-fired clay product sold for use in cats' litter boxes. This same or a similar material is also sold as a soil amendment. Supposedly, when mixed in clay soils it helps bind the clay particles together.
The Schultz company sells what looks like the same product under several names: Multipurpose soil conditioner, Turface (until recently, sold by Profile), and a so-called "soil" for use in potting water-garden plants. Turface is used on baseball fields to dry up the base line running paths. The grain size of all three of these products is too small to be of any value for use in potting mixtures.
Oil Dri is a product sold in some hardware stores and auto stores for soaking up oil spills in garages.
Maidenwell (Diatomite in the U.S.) is sold in different grain sizes for horticultural use. Diatomite (diatomaceous earth) is imported from Australia. The grain size of these two products, which is about two to three times the size of commercial cat litter, is perfect as a potting medium for cacti and succulents because the products contain no organic material to cause rot and the grain size provides superior drainage.
Stalite, sold as VoleBloc, is an unrelated lightweight product made of shale. This gray rock is more angular than the Diatomite and is slightly larger. This product is mixed with organic materials to create a growing medium for "green roof" gardens, so this gives you an idea of how you might use the product. Mix it with commercial potting mixes for use in outdoor containers where it improves drainage without making the containers too heavy to move about.
