What is Topsoil?
A Topsoil for every purpose generally describes the many different interpretations of the term ‘topsoil’. Amended topsoil, native topsoil, organic topsoil, manufactured topsoil, class ‘A’ topsoil, weed-free topsoil, and sandy loam are all general terms used to describe topsoil with the intent of achieving a planting media which is more or less horticulturally suitable for some particular crop or intended use. In its simplest form, topsoil means just what it sounds like: soil from the top of the underlying earth that has had the benefit of years of organic decomposition as well as Mother Nature’s rain-soaked fortification and leaching over time. This transforms the surface into a dark, rich, living viable media that we all remember as the secret weapon in grandpa’s garden.
Topsoil in Southwest Gardening
Unfortunately, modern construction methods now practiced throughout most of the Southwest have left most of us with no topsoil in our yards at all, as heavy grading and manufactured fills have scraped our precious soil away. Sure, it is possible that you may have the good fortune to have reasonably good underlying soil that can be amended fairly easily in your yard, but the sad truth is that most of us are not that lucky.
For most of us, if we want to have even modest success with our yard we will need to acquire some topsoil to spread over our existing soil, even if we have already amended the underlying soil.
How Much Topsoil do You Need?
Here is where the challenge begins; what do I buy, where do I buy it, and how much do I buy? Most plantings require between 6 and 12 inches of topsoil, however most fruit and vegetable gardens require even more. The best possible source would likely be soil scraped up from some farmer’s bottomland and delivered to your yard, but in today’s world that is simply not available. Even if it was, it would not work the same in your yard as it did in the farmer’s field. So, today, most topsoil sold is created by amending sandy loam with organic matter (generally organic compost), and nutrients to create a finished product commonly referred to as Amended Topsoil.
It is important, though, to understand that placing good topsoil in your yard is just a foundation to be built upon as you move ahead with your garden. Just as Grandpa on the farm used to spread his chicken manure on the field and plow before he planted, soil in our gardens needs to be constantly replenished with organic fertilizer to replace the nitrogen used up by the plants and the decomposition process. We, here at Evergreen Nursery recommend Gro-Power. So, if you work your soil and regularly add good organic matter to your topsoil, you will have created a good base for that garden project!