Purple milkweed Indiana Dunes

Family:     Apocynaceae (Dogbane family)

Duration:  Perennial

Height:     up to 90 cm (up to 3 ft)

Blooming: June - July

 

Purple Milkweed

Asclepias purpurascens L. 

Stem: erect, stout, and usually has really fine hair but is sometimes smooth.  When broken, a milky sap comes out.  No branching, has a single stem.

Flowers: relatively large, 5-parted flower that spreads from a common point in clusters and blooms throughout the summer. Its color is a reddish purple to light or deep purple. The flowers smell fragrant.  The horns do not exceed the hood but are turning inward.  Usually, a plant has one or a couple umbels of flowers.

Leaves: simple, opposite leaves up to 15 cm (6 in) long.  They can be a little more elliptic or ovate-oblong in shape.  There is hair on the underside of the leaves and they usually have stems (pedicels) on the leaves that can be up to 2.5 cm (1 in) long.  Many times the leaves are slightly wavy.

Fruits: large follicles, which can be 15 cm (6 in) long, that are soft.  They split open releasing the brown seeds which are attached to white hairs called a "coma".

Sun: Full sun to partial shade.  Found more in savanna type systems.

Asclepias purpurascens at Indiana Dunes

Comments: Purple milkweed is one of the showiest milkweeds in Northwest Indiana.  It looks very similar to the common milkweed (Asclepias syriaca); however purple milkweed has their flower heads (umbels) usually on the top of the plant instead of the axils of the leaves.  The follicles (seedpods) are distinctly different in that common milkweed's fruits are very warty and fat, whereas purple milkweed follicles are long and skinnier without those warts. 

Etymology: The genus Asclepias was named by Carl Linnaeus after the Greek god of medicine, Asclepius.  The name, purpurascens, means, "kind of purple" due to the color of the flowers.

all photos by Nathanael Pilla