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Uses of Sphagnum Moss

By Sharon Sweeny ; Updated September 21, 2017
Partially decayed sphagnum moss is a popular soil amendment for home gardens.
Moss image by Vasilyi Sidorchuk from Fotolia.com

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.


About the Author


Sharon Sweeny has a college degree in general studies and worked as an administrative and legal assistant for 20 years before becoming a professional writer in 2008. She specializes in writing about home improvement, self-sufficient lifestyles and gardening.