Prehistoric Plant, Modern Miracle

As the last Ice Age ended about 10,000 years ago and the Laurentide Ice Sheet receded out of what is now west central Wisconsin, long-fibered sphagnum moss marshes, long frozen, were uncovered. Amidst American mastodons, mammoths and bison, prehistoric peoples discovered the unique, valuable qualities of long-fibered sphagnum moss and put the plant to use to improve their lives.

The Magic of Sphagnum Moss

Initially, the dead and decaying sphagnum moss, or peat, was dug up, dried and burned as fuel. There is also evidence that the live moss was baked, producing a bread-like food that had very little taste and was nearly void of nutrients. However, early humans soon discovered much more beneficial uses for long-fibered sphagnum moss.

As sphagnum moss dies off, it releases sphagan, a natural sugar which neutralizes nutrients and starves bacteria. The harvested moss is acidic and sterile. Because of this sterility, sphagnum moss is free of weeds, insects and disease, making it an important tool in Paleo-Indian people’s wound care and infection prevention. There is evidence that prehistoric people carried moss with them on hunting excursions to create medicinal compresses to help heal injuries. During World War I, soldiers used moss with great success to treat wounds when sterile bandages were not available.

Because sphagnum moss holds water without puddling, recreational fishermen have used it to keep bait worms happy and moist.

How Sphagnum Moss Grows and is Harvested

Wisconsin has 1,000 acres of sphagnum moss marsh, the largest marsh in the world. Sphagnum moss has no root system, absorbing water and nutrients through its leaves. It grows in dense clumps by sporing.

When the moss’s leafy stems are about 10-12 inches long, it is carefully harvested. “Mossers” rake the moss by hand, or use a machine that delicately removes top growth, leaving the marsh habitat intact. The moss is then dried and packaged for a variety of uses, including seed starting medium, soil cover and soil conditioner, Living Wreaths, airlaying kits and totems.

It takes about 5 to 10 years for the moss to grow back to harvestable size, depending upon winter temperatures and hard freezes.

Mosser Lee does not harvest the sphagnum peat, the decomposed moss that is compressed below the living moss. Doing so would interrupt the sporing process, resulting in the loss of the living moss.

Sphagnum Moss Horticultural Uses

Even 10,000 years ago, sphagnum moss was put to use in horticultural methods. Because the moss holds nearly 20 times its weight in water and doesn’t puddle when drainage is provided, it’s an ideal soil amendment. Primitive humans used sphagnum moss as a soil conditioner as communities moved away from hunter/gatherer societies towards agricultural societies.

Sphagnum moss is invaluable in keeping plants and flowers in wreaths, window boxes and hanging baskets, both indoors and out, hydrated and thriving. The moss is a vital component to creating kokedama, decorative hanging balls of soil, moss and plants created in the Japanese tradition. Sphagnum moss is an environmentally safe and sustainable way to keep floral arrangements fresh and beautiful, eliminating the need for floral foam which is not organic, compostable or recyclable, breaking down into harmful microplastics.

Commercial nurseries use sphagnum moss to mix with soil and pack live plants, helping to ensure roots do not dry out and die during transport. It’s also used to store bulbs and other tubers that need to be dug out and protected from winter weather.

Sphagnum moss is an ideal medium for airlayering, as roots grow easily in the lightweight moss with almost no risk of infection.

Sphagnum Moss and Seed Starting

For commercial nurseries and hobby gardeners alike, the most valuable use of sphagnum moss is as a seed starting medium. Using a technique created by U.S. Department of Agriculture horticulturists V.T. Stoutmeyer, Albert W. Close and Claude Hope, pulverized long-fibered sphagnum moss has an incredible germination rate. Details of this method are outlined in Leaflet 243, “Sphagnum Moss for Seed Germination.” Advantages of using long-fibered sphagnum moss as a seed starting medium include:

  • 97% seed germination rate
  • Reduces need for watering
  • Keeps seed moist without puddling
  • Antibacterial properties eliminate pathogens and fungi that kill seedlings
  • Stronger and more uniform root structure remains intact during potting up and transplanting
  • Growth can be controlled due to sterility of medium

For detailed instructions and the science of starting seeds with sphagnum moss, click here.

Today, Mosser Lee in Wisconsin is the only domestic, U.S.-based grower and producer of long-fibered sphagnum moss and related horticultural products. Mosser Lee is a family-owned farm, employing local residents. Because Mosser Lee deeply respects our responsibility as stewards of the Wisconsin marsh system and harvests carefully and thoughtfully, this long-fibered sphagnum moss marsh is a renewable resource. With deliberate conservation and wise management, this marsh system can continue producing compostable, sustainable horticultural products for thousands of years to come.