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Common milkweed has a long history as a natural remedy—and has many other uses, too! Plus, milkweed is the food of our beautiful monarch butterflies. Learn about this surprisingly useful native plant.
Common milkweed (Asclepias syriaca) is the best known of the 100 or so milkweed species native to North America. The name “common” fits the plant well because when not in bloom, it goes pretty much unnoticed, growing humbly along roadsides, in fields, and in wastelands.
Natural Remedies with Milkweed
Once upon a time, milkweed was commonly used in a number of natural remedies:
Native Americans taught early European settlers how to properly cook milkweed so that it could be safely eaten. (See note below.)
The milky white sap was applied topically to remove warts, and the roots were chewed to cure dysentery.
Infusions of the roots and leaves were taken to suppress coughs and used to treat typhus fever and asthma.
Note: Today, experienced foragers may enjoy eating young milkweed sprouts, which resemble asparagus, but ONLY if they are properly identified (there are poisonous lookalikes, such as dogbane) and properly prepared (boiled). Some common milkweed plants (A. syriaca) are mild-tasting, while others are bitter. If you are new to foraging, have an expert help you identify, gather, and prepare the plant properly before eating. As with any herb, take only a small amount at first, to be sure that you don’t have an adverse reaction.
Caution: Do not get milkweed sap in your eyes (such as rubbing your eyes after touching the sap); wash your hands thoroughly after handling the plant. Also, some people may develop an allergic reaction when the sap touches the skin.
Is Milkweed Poisonous?
Beneath its dull, gray-green exterior, milkweed is slightly toxic.
Inside the plant is a sticky white sap that contains a mild poison; its bitter taste warns away many of the animals and insects that try to eat its tender leaves.
Certain insects, including monarch butterfly caterpillars, are immune to the toxin. By feeding almost exclusively on milkweed leaves, they are able to accumulate enough of the poison in their bodies to make them distasteful to predators which means that milkweed is a great plant for butterflies.
The nectar in all milkweed flowers provides valuable food for butterflies, bees, and other pollinators. Butterflies don’t only need nectar, but also need food at the caterpillar stage. The leaves of milkweed plants (Asclepias spp.) are the ONLY food that monarch caterpillars can eat! And monarch butterflies need milkweed to lay their eggs. With shifting land management practices and pesticide use, we have lost much milkweed from the landscape. This has led to a 90% decline in the number of eastern monarchs in a just single decade.
Fun Facts About Common Milkweed
The stems’ tough, stringy fibers were twisted into strong twine and rope, or woven into coarse fabric.
Inside milkweed’s rough seed pods is another wonderful surprise: The fluffy white floss, attached to milkweed’s flat brown seeds, could be used to stuff pillows, mattresses, and quilts, and was carried as tinder to start fires.
During World War II, the regular material used to stuff life jackets was in short supply, so milkweed floss was called for as a substitute—it is about six times more buoyant than cork!
Over the years, researchers have investigated growing milkweed for paper-making, textiles, and lubricants, and as a substitute for fossil fuels and rubber. Although these experiments were found economically unfeasible at the time, perhaps they should be revisited, given the rising costs of fuel and other materials.
In current research, a chemical extracted from the seed is being tested as a pesticide for nematodes.
We doubt if this surprisingly useful plant will run out of surprises anytime soon! Common milkweed seeds grow well in just average soil. Scratch milkweed seeds directly into the soil in the fall. The following summer, seedlings will emerge.