Swamp Milkweed, Asclepias incarnata L., Native Minnesota Wildflower plant, Eloise Butler Wildflower Garden

Swamp Milkweed is an erect native perennial that can reach to six feet in height with divided branches toward the top. Stems are green, circular and without hair. Like most milkweeds, they contain a milky juice which is toxic. Leaves are lance like with pointed tips, stalkless to clasping, up to 3" long, opposite and with smooth margins and smooth medium to dark green surfaces. Inflorescence: The striking flowers are in erect umbels at the top of the stems. Milkweed flowers, when open, have five erect hood-like nectaries with the petal parts bent downward. These vary in color in this species from pink to rosy-purple, but the hoods are a lighter shade. The hoods each have a small horn on the inner side that curves inward and in this species is much taller than the hood. Each flower is about 3/8" tall and 1/4" wide. Eloise Butler explains the function of these parts in her notes below. The pollen of the milkweed is not in the form of free grains attached to an anther, but is contained in a waxy sac called a "pollinium" [plural - pollinia] with each sac having about a few hundred grains. These are located along vertical grooves within the flower and they attach to the body of an insect, such as a bee, and are then carried from flower to flower by the insects resulting in pollination. Any insect large enough to remove the sac can fertilize another plant. Flowering is usually not until mid July and continues well into August. Seeds: Fertile flowers develop a slender green pod (a follicle) held erect on erect stalks. The pod turns brown at maturity and contains a large number of flat brown seeds attached to long white silky hairs. When the pod splits, these are dispersed by wind.

Habitat: Swamp Milkweed is a common plant of bogs, swamps and wet places, with full sun. It grows from a rhizomatous root system and adapts to loamy, sandy or clay soils but does not tolerate well dry conditions. Comparisons: The showy erect umbels of flowers and the branching at the top of the plant will readily identify this species of milkweed. Names: The genus name, Asclepias, is for the Greek god of healing. The species name, incarnata, is Latin for flesh, referring to the color of the flowers at certain times.

	Plants of the Eloise Butler Wildflower Garden
	Common Name	Scientific Name	Plant Family	Garden Location	Prime Season
	Swamp Milkweed	Asclepias incarnata L.	Milkweed (Asclepiadaceae)	Woodland - Bog	Early to Late Summer
Other names and notes	Swamp Milkweed is an erect native perennial that can reach to six feet in height with divided branches toward the top. Stems are green, circular and without hair. Like most milkweeds, they contain a milky juice which is toxic. Leaves are lance like with pointed tips, stalkless to clasping, up to 3" long, opposite and with smooth margins and smooth medium to dark green surfaces. Inflorescence: The striking flowers are in erect umbels at the top of the stems. Milkweed flowers, when open, have five erect hood-like nectaries with the petal parts bent downward. These vary in color in this species from pink to rosy-purple, but the hoods are a lighter shade. The hoods each have a small horn on the inner side that curves inward and in this species is much taller than the hood. Each flower is about 3/8" tall and 1/4" wide. Eloise Butler explains the function of these parts in her notes below. The pollen of the milkweed is not in the form of free grains attached to an anther, but is contained in a waxy sac called a "pollinium" [plural - pollinia] with each sac having about a few hundred grains. These are located along vertical grooves within the flower and they attach to the body of an insect, such as a bee, and are then carried from flower to flower by the insects resulting in pollination. Any insect large enough to remove the sac can fertilize another plant. Flowering is usually not until mid July and continues well into August. Seeds: Fertile flowers develop a slender green pod (a follicle) held erect on erect stalks. The pod turns brown at maturity and contains a large number of flat brown seeds attached to long white silky hairs. When the pod splits, these are dispersed by wind. Habitat: Swamp Milkweed is a common plant of bogs, swamps and wet places, with full sun. It grows from a rhizomatous root system and adapts to loamy, sandy or clay soils but does not tolerate well dry conditions. Comparisons: The showy erect umbels of flowers and the branching at the top of the plant will readily identify this species of milkweed. Names: The genus name, Asclepias, is for the Greek god of healing. The species name, incarnata, is Latin for flesh, referring to the color of the flowers at certain times.