Sphagnum peat moss has long been considered an important component of potting soils and seed starting mediums. It holds many times its own weight in water and releases it slowly as soil dries out.

Peat moss is well-loved by gardeners, but it might be better to leave it in the ground. Try these alternatives for many of peat's most important attributes.

Peat moss is the decaying plant matter that forms under sphagnum moss. As sphagnum moss grows, it layers upon itself, collecting and compacting dead matter beneath the living layer.

Bogs may be many feet deep with sphagnum on the top and decaying “peat” on the bottom. Moss is a sustainable crop as long as it is allowed to regenerate — typically more than 10 years.

Sphagnum grows remarkably slowly (about 1/25th of an inch per year). With that figure in mind, it will take 3,000 years for new peat to reach the necessary depth for commercial mining.

Canadian Sphagnum Peat Moss is very porous, so it holds nutrients as well as moisture. It takes centuries to form in very specific conditions typical of northern wetlands of Canada.

Make sure to purchase Canadian sphagnum peat in bales at your garden center and avoid bags that are labeled as just “peat moss.” Compost is also a wonderful addition to improve soil.

Peat, the ingredient that makes bagged soil light and spongy, comes from wetlands. Often labeled as sphagnum moss or peat moss, it became popular in the 1950s because of its versatility.