Compost can be broken into three basic types based on its quality and usage.
These are Biological, Commercial, and Industrial.
Biological - This is the highest quality compost and therefore the most beneficial in improving soils, preventing disease, making compost tea, etc. This is the product that experienced gardeners often call black gold because it is so valuable to plants. The bag will have holes in it so that air can enter and the beneficial microbes can breath and be kept alive. This compost will typically sell retail for $12-14 per bag (40 lb.).
Commercial - This is a middle grade of compost made from sewage sludge, construction debris, etc. It will be in a sealed bag and may have a sour or stale odor. The better manure based composts may be found here. This compost will typically sell retail for $4.99-8.99 per bag (40 lb.).
Industrial - This is the lowest grade of products called compost. It is made from industrial wastes like boiler ash. It is often very black and sometimes will rub off in your hand. It often contains fillers like sawdust and rice hulls which are chemically burned black from the industrial waste. It may be extremely alkaline and high in toxic salts. This product will typically sell retail for $2.99-3.99 per bag (40 lb.).
Nature's Way Resources
101 Sherbrook Circle Conroe, Tx 77385
(936) 321-6990 Metro (936) 273-1200 Conroe (936) 273-1655 Fax