Asclepias incarnata (Swamp Milkweed)

USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner’s Sons, New York. Vol. 3: 26.


Where Commonly Found: Swamps, shores, wet meadows, river bottomlands, CT, ME, MA, NH, NY, RI, VT.
How to Identify:
(For unfamiliar words: Wikipedia Glossary of Botanical Terms).
Go Botany Key to Asclepias incarnata.
Missouri Botanical Garden description of Asclepias incarnata.  Click on more images.

Flower Color:  Mauve pink to rose-purple
Flower Type:  Umbels, radial petal-like parts bending down, each flower having 5 erect 1/8″ hoods with curved horns.  Distinct seed pod, split open to expose silky haired seeds that float in the wind.Flower Time:  Early July to mid August.
Leaf Arrangement:  Opposite with 2 leaves per node along erect, clump-forming stems, usually hairy, that exude milky sap when cut. 
Leaf Type:  Simple, lance-shaped leaves, smooth edge, usually tapered at tip, 3″-6″ long with lateral veins projecting upwards, making an acute angle with the midveib,
Height:  4′- 5′
Seed Collection:  Collect pods, an erect follicle, 2-1/2″ – 4″ long, as yellowing and splitting, avoid pods with weevil larvae frass, signs of damage, and/or small entry holes, as pod will likely be dead.  Open healthy pods and remove the ripe brown seeds from the wet down.  Store dry seeds cool, dry or in refrigerator.

Attracts:  Bees, Butterflies, Larval Host
Use:  Garden, Rain Garden, Naturalizing
Light:  Full Sun
Hardiness Zone:  3 to 6  USDA Zone Map
Soils:  Moist to Wet
Notes:  Swamp milkweed, is tolerant of well-drained soils, very attractive to butterflies, and a nice cut flower.
Native to Native to all US but the West Coast:  Biota of North America Program (BONAP) – North American Plant Atlas (NAPA).

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