Spongy brown peat moss is a well-known gardening and farming material used to amend soil. With its increased water retention and nutrient properties, adding soil peat moss has many benefits, but it should not be used in balanced or acidic soil or for plants that prefer an alkaline environment. Understanding the proper uses of soil peat moss and where to use it can help a gardener get the most out of adding peat moss to soil.
Peat moss is dried, partly decomposed moss. Peat moss occurs naturally in soil in rainy, wet areas. Peat moss can be purchased in garden and agricultural supply stores. When sold by itself, peat moss is a spongy, brown, gray and yellow-green mass of curly strands of moss.
Peat moss soil is soil that is mostly peat moss. A dark brown subsoil, a layer of soil located beneath the topsoil, indicates the presence of peat-dominated soil. Soil which is predominantly peat moss but which contains a large amount of sand would be called sandy peat soil.
Peat moss can increase the water retention of soil. When mixed into a soil mixture as an amendment, peat moss is a viable source of organic matter. An acidic additive to the soil, peat moss is best used to reduce the potential of hydrogen (pH) of an alkaline soil environment. Plants which thrive in an acidic soil can benefit from soil with peat moss.
Usually called sphagnum peat moss at the market, this product is usually a combination of multiple types of mosses. Sphagnum moss is sold milled and unmilled. For soil peat moss, milled sphagnum peat moss is the correct variety to use for gardening. Sphagnum moss and unmilled sphagnum peat moss are treated differently from milled sphagnum peat moss and are usually used by florists or crafters.
Though it is commonly used as a protective top layer of mulch, this is often a poor choice for soil peat moss. Gravel, wood chips and grass clippings are more effective mulch materials that harbor better soil drainage and water distribution. Its water repellent properties make peat moss an inferior mulching material.