Asclepias perennis
USDA, NRCS. 2018. The PLANTS Database (http://plants.usda.gov, 28 March 2018). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Illustration: 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: 31.
What is Aquatic Milkweed?
Physical Characteristics
Leaves:
- Opposite
- Elliptical to sword-shaped
- 2-5.5 inches long
- Up to 0.59 inches wide
- Leaf stalks up to 0.59 inches long
Flowers:
- Single at upper nodes
- Many flowered
- Small
- White in color, sometimes with light pink
Fruit:
- Dry
- Opens on one side to release seed when ripe
- 1.5-2.75 inches long
- 0.39-1 inches wide
- Smooth
Seeds:
- Oval-shaped
- About 0.59 inches long
Stem:
- Slender
- 1-1.75 feet tall
- Branching only from base
Roots:
- Short rootstalks
Where Does it Grow?
Aquatic milkweed is an obligate wetland plant for the Gulf Coast, Midwest, and Great Plains regions and can be found in low swampy areas, woods, and ditches.
Bloom Color: White , Pink
Bloom Time: May , Jun , Jul , Aug , Sep
Pros and Cons of Aquatic Milkweed
Milkweed is the only plant eaten by Monarch butterfly caterpillars, one of the reasons their numbers are dropping is the loss of space for milkweed to grow due to mowing or pesticides.
Flowers are beneficial to native bees.
Submerged portions of all aquatic plants provide habitats for many micro and macro invertebrates. These invertebrates in turn are used as food by fish and other wildlife species (e.g. amphibians, reptiles, ducks, etc.). After aquatic plants die, their decomposition by bacteria and fungi provides food (called “detritus”) for many aquatic invertebrates.