Are you thinking of adding topsoil to your landscape. If so, there are several things that you should consider.
First of all let’s start with the definition of topsoil?
The simple answer is that topsoil is the topmost layer of soil. A narrower definition may be the top layer of NATIVE soil. This term may also apply to good quality soil sold at nurseries and garden centers. There is an expectation that topsoil contains adequate amounts of organic matter. Organic matter makes the soil darker and people often assume that darker topsoil is better. Don’t confuse topsoil with potting soil or bedding mix. The latter cost more and have more specialized applications as their name implies.
Why do you want to buy topsoil?
Topsoil may be used to improve or add to your landscape; to build up low spots, make raised beds, or back-fill construction areas. It is used to improve existing soil either as top-dressing on lawns, or tilled into garden areas. Sometimes with existing heavy clay, an addition of a raised bed filled with topsoil is viable alternative.
Where do you get topsoil?
If you are starting new construction on a lot, and the native topsoil is good, consider dozing of the top six inches or so into a convenient pile. This will provide a cheap and ready source of topsoil when construction is completed.
Another suggestion is to improve your own existing topsoil by adding amendments such as compost, sand or clay to improve the characteristics of the existing soil. Compost adds vital organic matter. Sand improves drainage of heavy clay soils, and clay improves retention of water and soil nutrients in sandy soils.
If it is necessary to purchase topsoil, consider the source. Most nurseries can provide good quality topsoil. Their reputation depends on it and they know if customers are satisfied with it.
For small projects, the most convenient, but most expensive way to get top soil is by the bag. When you consider trucking cost, this may be the best choice for very small projects.
There are trucking companies that specialize in supplying soil, gravel, and stone, etc. to nurseries, businesses and home owners. Besides topsoil, they provide topsoil mixes that are fortified with organic and inorganic materials. An example of a local proprietary mix consists of topsoil, mushroom compost, ground pine bark plus sand potting mix. Each component contributes to the physical and fertility characteristics of the mix. Selecting a soil-mix will cost a little more but may well be a better choice in the long run.
There are questions you might ask before placing your order: but don’t expect to get the answers to all of you questions from any given supplier. Ask around, get a recommendation, and do some research before investing a lot of money in a load of topsoil.
- What is the pH of the topsoil? Most plants prefer a pH of 6.2 – 6.8
- What is the percentage of organic matter? Three percent is good, five percent is excellent.
- What are the physical properties of the soil? Good topsoil is a mix of clay, sand, silt, and organic matter. An excellent web sit describing the physical properties of soil is http://www.ext.colostate.edu/mg/gardennotes/214.html
- If you are concerned about the physical properties and fertility, further testing on your part may be necessary. Fertility may be determined by submitting a topsoil sample to a Soil Testing Lab. Details on how to collect and submit samples can be obtained from your local county extension office. Depending on the season, it may take several weeks to get the results, so plan ahead and start early.
- Be aware that poor quality topsoil may be un-screened; screening takes out unwanted herbicide and pesticide residues, weed seeds, or other undesirable products.
- During delivery, soil compaction from heavy truck-loads may occur. To minimize compaction damage to existing soil, plan for a suitable route and location for the topsoil to be dumped.
- You may elect to order a small amount of topsoil at first to see how well it performs at your location.