Leaflet No. 243, “Sphagnum Moss for Seed Germination

Leaflet No. 243, Sphagnum Moss for Seed Germination was published by the U. S. Department of Agriculture in 1944. This science of seed starting information, authored by V.T. Stoutemeyer, associate horticulturist, Albert W. Close, principal scientific aide, and Claude Hope, assistant horticulturist, Division of Plant Exploration and Introduction, Bureau of Plant Industry, Soils and Agricultural Engineering, Agricultural Research Administration, is still relevant and fresh today.

To read the pamphlet, click here.

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.

2022 Spring Milkweed Project

2022 Milk Weed Project for Monarch Butterfly Restoration

The Eastern Monarch is on the Move!

Spring is here and the Eastern Monarch is on the move and milkweed is starting to sprout. Every year, these unique pollinators travel from the Mountains of Mexico to the Great Lake Region. Twice a year butterflies embark on a 3,000-mile journey. The butterflies have a short lifespan, born in Mexico they have never been to the US or Canada yet take on this journey like their ancestors many generations before them. The Eastern Monarch is encouraged by environmental factors to move north where last year we saw possibly their great great grandparents munch on milk weed, flutter from flower to flower and eventually start the life cycle all over again

Over the past 20 years both Eastern and Western Monarch Populations have plummeted by
80% to 90% sounding the alarm to environmentalists and advocates like Mosser Lee to aid in conservation efforts like habitat restoration projects. Milkweed has decreased by 21 percent in
the U.S. between 1995 and 2013, and nearly 165 million total acres of milkweed have been lost
to pesticide-intensive agriculture and development. Reversing that trend by actively restoring
milkweed and other pollinator habitats is critical to ensure the long-term survival of the
monarch butterfly.

Plant Milk Weed for Pollinators

Mosser Lee offers free Milkweed seeds for anyone who wishes to help with this effort. As Monarch Butterflies will only lay their eggs on the milkweed plant this effort is critical for population growth. Milkweed is important to other pollinators and is an important addition to local eco systems, it also smells wonderful when in bloom.  Check our our past Efforts on Monarch Habitat Restoration. 

To receive your free Milkweed seeds from Mosser Lee, simply click here and we will mail them to you when the season is right. Milkweed seeds do need a chilling period before germinating so make sure to make your request today.

Request Milk Weed Seeds

Request Milk Weed Seeds

Milk Weed Seed Request


5 Ways to Help Butterflies and Pollinators this Spring

These efforts are starting to pay off Eastern and Western populations seem to be on the rise but due to several constraints of the past few years data collection in both over wintering locations has been challenging.  We still need your help. Here are 5 things you can do to create butterfly friendly environments in your garden.

Milk Weed
  1. Start by planting Milkweed for your pollinator friends. Milkweed seeds are best planted in the fall and winter months because they need a period of cold stratification, however it’s not too late.  Once you receive your seeds, simply place them in you refrigerator for 4-6 weeks for cold stratification.  This gives you plenty of time for planting. 

2.     Get kids involved.  This is an ongoing problem, and like many environmental issues the education and involvement of kids is our best chance for future conservation.  It’s a great time to teach kids about the lifecycle of the monarch.  There are wonderful resources available to teach kids what to look for and how to monitor butterflies in their natural environment. We caution you against bringing in wild butterflies to raise indoors as the ultimate goal is for these butterflies to be able to be sustainable without human intervention.  Experts in monarch research have raised some valid concerns about commercial raising of Monarch to supply the common butterfly kit focused on a lack of genetic diversity and an increase of parasites.

Kids and Butterflys
Say no to pesticides

3.  Cut ties with herbicides. Many pesticides contain glyphosate, a herbicide that kills milkweed. Milkweed is the only plant monarch larvae eat, and the only plant the monarch will lay its eggs in. Without milkweed, the monarch butterfly would cease to exist.

4.     Start a pollinator garden.  A pollinator garden is simply a garden that is focused on attracting pollinators.  Just add native plants that produce a significant amount of pollen and nectar.  You’ll enjoy how wonderful they smell through the growing season. 

Plant a Pollinator Garden
Share your Butterfly Success

5.  Spread the word! Social media has its faults but it’s great for spreading the word on environmental causes.  Make sure to post pictures of your growing gardens and your butterfly visitors.  Let your friends know about the need for more milkweed while at the same time beautifying your feed and don’t forget to tag us, we’d love to share your garden wins!

Make sure to join us in our community efforts by liking and sharing on social media.  Follow us on Facebook, Instagram and Pinterest