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Uses of Sphagnum Moss

Moss image by Vasilyi Sidorchuk from

Harvested primarily in Canada and North America, sphagnum peat moss (Sphagnum andersonianum) is an all-purpose soil amendment that can also be used alone in certain horticultural operations. The peat moss sold in garden centers is the partially decayed remains of plants grown in high-acid peat bogs. The high-acid content of the water slows down or halts the decay process, resulting in a tough, stringy, fibrous product for use in your garden.

Container-Grown Plants

Plants grown in containers require a light, aerated soil mixture capable of retaining a lot of water. Adding sphagnum moss to the soil of potted plants does the trick. Its stringy, fibrous texture creates air pockets in the soil; it can hold up to 20 times its weight in water.

Improves Garden Soil

When added to garden beds, sphagnum moss will create a more desirable growing medium whether your garden soil is clay or sand. Peat moss loosens up heavy clay soils, creating air pockets between the tightly packed microscopic clay soil particles, helping it to drain more rapidly and keeping the plants' roots from becoming waterlogged. At the same time, it increases the soil's ability to retain moisture and nutrients, which tend to drain away too rapidly in sandy soils.

Starting Seeds

Because it contains specific fungistatic substances, sphagnum moss is widely used for indoor seed starting, according to Texas A&M University Extension. The fungistatic substances in sphagnum moss inhibit the development of a fungal disease called “damping off,” which is always fatal to small seedlings. It is thought to be present in most soils and is nurtured by the warm, moist environment conducive to seedlings' germination and early growth. It most often strikes seedlings approximately 7 to 10 days after germination and emergence.

Sphagnum Peat Moss?

Perhaps the most common use for sphagnum peat moss is as a soil amendment. The material helps loosen hard, compacted soils while improving drainage around plant roots. One way to save water in your garden is by adding sphagnum peat moss to the soil. Peat moss also reduces the amount of runoff, or water that carries away important nutrients that would otherwise be used by root systems. There are also concerns that mosses release carbon dioxide that would otherwise be trapped in the bogs, and that the use of peat moss may contribute to global warming. Sphagnum peat moss is generally most available at the beginning of the gardening season, usually early spring in most places. Peat moss is carried by most home improvement stores, as well as by specialty gardening shops and farm supply stores.

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