Common Milkweed — An Insect Delicatessen

• Nature News | Marlene A. Condon
• November 7, 2023

Autumn’s the time of year to look for the dried seedpods of Common Milkweed. This food plant of the Monarch Butterfly often comes up along rural roadsides, where it’s likely to get cut by the Virginia Department of Transportation when it performs its fall mowing. However, short plants might get missed by the mower blade, while taller plants might get pushed aside rather than cut.

If you are lucky and find a pod (no need to take home more than one), you can spread its seeds where you’d like the plants to grow next year. And if you are truly lucky, a Monarch will alert you next spring to the new plants in your garden as she lays her eggs.

Common Milkweed (Asclepias syriaca) is a flowering plant that often comes up in dry fields where it typically grows 3-5 feet tall. It starts to bloom in early summer, and if you smell the uniquely shaped flowers, you’ll be rewarded with a wonderful scent worthy of expensive perfume.

The overall impression of these plants from a distance is one of ungainliness and coarseness, so many folks don’t like to plant them in manicured gardens. But a close look reveals lovely flowers that attract a great many pollinators.

Blooming sometime in June, they attract numerous species of butterflies to the goblet-shaped flowers that hold a generous amount of nectar. You might catch a glimpse of Silver-spotted Skippers, Great Spangled Fritillaries, Zebra Swallowtails, American Ladies, Tiger Swallowtails, Eastern Tailed Blues, and Spicebush Swallowtails. You could even spot an unfamiliar species! On June 18, 1999, I saw my first-ever Variegated Fritillary feeding at Common Milkweed in my yard. It spent an afternoon in my milkweed patch before disappearing. And, of course, milkweed could bring in the Monarch whose caterpillar prefers this species of milkweed.

Bumblebees love milkweed nectar, although they are sometimes killed when their legs become trapped inside a flower slit. You can see these slits if you look closely at the flowers. Little bags of pollen are within each slit and they become attached to an insect’s leg if it slides into the opening. The insect then carries the pollen to another milkweed plant where it fertilizes a flower if all goes well. If this plan fails, however, you could notice a dead or dying bee caught on a flower head. The fertilization process is so complex in Common Milkweed that very few flowers ever get fertilized. From each cluster of up to 75 flowers only two seed pods will normally develop.

Numerous other kinds of interesting insects can be found on Common Milkweed, including orange aphids! In June, orange-and-black insects appear on the plants. Called Large Milkweed Bugs, they suck the juices of developing seeds, which kills the seeds and thus helps to keep Common Milkweed from overpopulating an area. You could also get to see the Small Milkweed Bug that is black-and-red and serves the same function of limiting plant numbers.

Consider Common Milkweed an insect delicatessen!

Marlene A. Condon is the author/photographer of “The Nature-friendly Garden: Creating a Backyard Haven for Plants, Wildlife, and People” (Stackpole Books; information at www.marlenecondon.com). She writes a blog called “In Defense Of Nature.”