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Topsoil vs. Com-Til

By Andrea Krochalis ; Updated September 21, 2017
Commercial products for composting, such as Comtil, may have the appearance of mulch.
compost surface. image by mdb from Fotolia.com

Comtil Compost is a commercial product made by the City of Columbus, Ohio from the residual bio-solids after processing at the wastewater treatment plant. It is combined with yard waste and wood chips. The product is used as a soil amendment. Topsoil is the uppermost layer of soil and contains organic matter from normal decay of fallen leaves and other naturally occurring materials. This layer may include soil tilled for cultivation. Topsoil is generally composed of 2 to 10 percent organic matter.

Topdressing Soil

Both commercial products such as Com-Til and natural or homemade compost are used for topdressing soil. This is a process of amending the pH balance, texture or nutrient mixture of the soil for a specific use or crop. Compost will help break up a clay-based soil so that there is less compactness and greater aeration. Adding organic material provides nutrients which improve growing conditions for crops and plants.


Com-Til is one of the commercial products that fertilize soil and help repurpose bio-solids as fertilizer. It also serves as a soil conditioner and as a mulch. The nutrients in Com-Til will decompose and enrich the soil as a compost material. The product can be used as a mulch around plants to help retain moisture. This provides a decorative look to landscaping. Such products serve all three functions of conditioner, fertilizer and mulch.


Gardeners have made home compost for centuries. Kitchen scraps, leaves and grass clippings are mixed with a bulk such as wood chips. The addition of manure will increase the heat of the mixture and help destroy weed seeds and pathogens that simple decomposing does not destroy. These materials will mature into hummus, a rich soil. Meat, dairy, diseased plants and pet wastes should not be added to compost. Turning or stirring compost will assist in the curing process.


The heat of decaying materials will assist in pasturing compost mixtures. Mixtures can be sifted through screens to provide a uniform size of components. Most commercial products are tested for pathogens. Many localities offer mulch and compost to residents. The private sector produces many commercial products with added value. Home composting is a way to reduce and reuse food and yard waste products.


Commercial compost is sold at home gardening stores in bags or by private or public vendors in bulk amounts and truckloads. Prices vary according to the level of processing and amendments added, as well as by amount. The selection of a specific product is matched to the condition and planned use of the soil.