Common Milkweed, Common Silkweed, Milkweed, Silk Grass, Silky Swallow Wort, Virginian Silk
Asclepias syriaca, commonly known as Common Milkweed, is a robust perennial native to North America. As one of the most well-known milkweed species, it plays a critical role in supporting monarch butterflies and other pollinators. This plant thrives in meadows, roadsides, and open fields, where it spreads readily through underground rhizomes, forming dense colonies. Its fragrant, globe-shaped flower clusters and broad leaves make it an excellent choice for wildlife-friendly gardens.
Milkweed plants belong to the Apocynaceae family, which includes other flowering plants such as oleander, hoya, plumeria, and the desert rose.
Common Milkweed is a hardy, rhizomatous perennial known for its domed clusters of fragrant, pinkish-purple, star-shaped flowers that bloom from early to late summer. A magnet for butterflies and bees, its nectar-rich blooms appear in the upper leaf axils of sturdy, upright stems. Thick, oval-shaped green leaves with striking red veins add to its appeal. In fall, prominent seed pods split open, releasing silky-haired seeds. Easy to grow, this fast-spreading milkweed thrives in gardens and natural settings.
Common Milkweed is widely distributed across North America, from Canada to the eastern and central United States. It thrives in prairies, fields, roadsides, and disturbed areas, where it naturally regenerates and spreads.
Unlike Swamp Milkweed (Asclepias incarnata), which prefers moist environments, Common Milkweed tolerates drier, sandy, and rocky soils, making it highly adaptable.
Spreads aggressively through rhizomes, forming extensive colonies. May also self-seed if seed pods are not removed before they split open and release seeds. Its vigorous growth can make it challenging to control, so it’s best planted in areas where its spreading nature is welcome.
Flower Color: Dusty pink to lavender
Bloom Time: Long-lasting bloom period from early to late summer
Fragrance: Very strongly and sweetly scented
Flower Shape: Large, 2- to 3-inch domed umbels of five-petaled flowers. Each cluster holds up to 100 star-like blooms, typically forming 1-3 clusters per stem. Flowers emerge from the leaf axils and often droop gracefully, adding to their delicate charm.
After flowering, Common Milkweed produces large, warty seed pods, which open in fall to winter, releasing wind-dispersed seeds with silky filaments.
The foliage serves as a larval host for monarch butterfly caterpillars, which feed exclusively on milkweed species.
Common Milkweed is hardy in USDA zones 3-9 and thrives in a wide range of climates. It is highly cold-hardy, tolerating frost and snow while also being drought-resistant once established.
Native Americans used milkweed fibers for textiles and cordage. During WWII, its seed coma was harvested for life jacket stuffing. Today, it’s used in pillows and blankets.
Common Milkweed is a powerhouse for wildlife, offering both habitat and food for various species. Monarch butterfly caterpillars rely on its leaves as a primary food source, while adult monarchs and other butterflies feast on its nectar-rich flowers. Native bees are frequent visitors, benefiting from the plant’s abundant nectar supply. This plant also attracts over 450 insects, which are known to feed on some portion of the plant.
Discover more plants that attract butterflies.
Common Milkweed has low toxicity but contains cardiac glycosides and resinoids, which can cause nausea, vomiting, diarrhea, weakness, and confusion if ingested in large amounts. Its milky sap may cause contact dermatitis and eye irritation. Toxic parts include flowers, fruits, leaves, roots, seeds, and stems. Harmful to humans, cats, dogs, and horses.
Monarch butterfly caterpillars store these toxins in their bodies, making them unpalatable to predators.
Common Milkweed is naturally resistant to deer due to its milky sap, which contains toxic cardiac glycosides.
Common Milkweed spreads aggressively through deep rhizomes and self-seeding. While beneficial in naturalized landscapes, it can quickly take over small gardens. To control its spread, remove seed pods before they open.
Common Milkweed is a must-have for pollinator gardens. With its fragrant blooms, essential role in monarch conservation, and easy-growing nature, it offers both beauty and ecological benefits. Whether planted in meadows, prairies, or roadside habitats, this resilient wildflower is a vital component of native ecosystems.
Milkweed: Is it Right for Your Garden? Pros and Cons Explained
Common Milkweed seeds require cold stratification to break dormancy.
Common Milkweed is generally pest-resistant, but it may attract aphids. These can be left alone, as they attract beneficial insects like ladybugs and lacewings, which keep their populations in check.
Hardiness |
3 - 9 |
---|---|
Heat Zones |
2 - 9 |
Plant Type | Perennials |
Plant Family | Apocynaceae |
Genus | Asclepias |
Common names | Common Milkweed, Milkweed |
Exposure | Full Sun |
Season of Interest | Summer (Early, Mid, Late) |
Height | 3' - 5' (90cm - 150cm) |
Spread | 8" - 1' (20cm - 30cm) |
Spacing | 12" (30cm) |
Maintenance | Low |
Water Needs | Low, Average |
Soil Type | Clay, Loam, Sand |
Soil pH | Acid, Alkaline, Neutral |
Soil Drainage | Well-Drained |
Characteristics | Fragrant, Showy |
Native Plants | United States, Northeast, Pennsylvania, Rhode Island, Vermont, Connecticut, Delaware, Maine, Massachusetts, Maryland, New Hampshire, New Jersey, New York, Wisconsin, Midwest, South Dakota, Ohio, Illinois, Nebraska, Missouri, Minnesota, North Dakota, Kansas, Indiana, Iowa, Michigan, Oregon, Pacific Northwest, Southeast, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, West Virginia, Alabama, Arkansas, Georgia, Kentucky, Southwest, Texas, Oklahoma, Rocky Mountains, Montana |
Tolerance | Drought, Deer, Dry Soil, Rocky Soil |
Attracts | Bees, Butterflies |
Garden Styles | Prairie and Meadow, Informal and Cottage |
Hardiness |
3 - 9 |
---|---|
Heat Zones |
2 - 9 |
Plant Type | Perennials |
Plant Family | Apocynaceae |
Genus | Asclepias |
Common names | Common Milkweed, Milkweed |
Exposure | Full Sun |
Season of Interest | Summer (Early, Mid, Late) |
Height | 3' - 5' (90cm - 150cm) |
Spread | 8" - 1' (20cm - 30cm) |
Spacing | 12" (30cm) |
Maintenance | Low |
Water Needs | Low, Average |
Soil Type | Clay, Loam, Sand |
Soil pH | Acid, Alkaline, Neutral |
Soil Drainage | Well-Drained |
Characteristics | Fragrant, Showy |
Native Plants | United States, Northeast, Pennsylvania, Rhode Island, Vermont, Connecticut, Delaware, Maine, Massachusetts, Maryland, New Hampshire, New Jersey, New York, Wisconsin, Midwest, South Dakota, Ohio, Illinois, Nebraska, Missouri, Minnesota, North Dakota, Kansas, Indiana, Iowa, Michigan, Oregon, Pacific Northwest, Southeast, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, West Virginia, Alabama, Arkansas, Georgia, Kentucky, Southwest, Texas, Oklahoma, Rocky Mountains, Montana |
Tolerance | Drought, Deer, Dry Soil, Rocky Soil |
Attracts | Bees, Butterflies |
Garden Styles | Prairie and Meadow, Informal and Cottage |
How many Asclepias syriaca (Common Milkweed) do I need for my garden?
Plant | Quantity | |
---|---|---|
Asclepias syriaca (Common Milkweed) | N/A | Buy Plants |
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Create a membership account to save your garden designs and to view them on any device.
Becoming a contributing member of Gardenia is easy and can be done in just a few minutes. If you provide us with your name, email address and the payment of a modest $25 annual membership fee, you will become a full member, enabling you to design and save up to 25 of your garden design ideas.
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