Swamp Milkweed

Asclepias incarnata

Swamp milkweed is a North American perennial found growing in swamps, along streams, and in moist meadows [1]. It reaches three to five feet in height and is topped with clusters of soft pink flowers that bloom through the middle of the summer. Swamp milkweed is a wetland plant that requires a moist or wet soil condition. Monarchs, swallowtails, bees, and many other pollinators are drawn to this plant for its sweet scent.

Swamp milkweed has been used by various Native American groups to treat respiratory and digestive ailments [2]. It was decocted and taken as a treatment for coughs, asthma, and bronchitis [2]. The plant was also used as a febrifuge and sweat inducer and was used for intestinal parasites. The action of the plant on the lungs also led to it being named white Indian hemp at one point.

Cardiac glycosides are present in swamp milkweed, just as in other milkweeds, and this chemical compound can be harmful to heart rate and can make the plant deadly if ingested in high doses [3]. Because of this, the herb is no longer used in modern herbalism except under direct supervision of an expert. The use history of the plant is still widely documented and is still regarded as potent.

Ecologically, swamp milkweed is incredibly important. The leaves are used as food by monarch caterpillars, and the blooms are a great nectar source for numerous pollinators throughout the middle of the summer [4]. Swamp milkweed has found a home in native garden and native restoration work, combining great looks with important function.

Swamp milkweed plants show us that plants with incredible power can also have a great responsibility to those who use them.

[1] Friends of Eloise Butler Wildflower Garden & Bird Sanctuary. “Swamp Milkweed, Asclepias incarnata.” https://www.friendsofeloisebutler.org/pages/plants/swampmilkweed.html

[2] Botanical.com. “A Modern Herbal | Swamp Milkweed (Asclepias incarnata).” https://www.botanical.com/botanical/mgmh/s/swamp101.html

[3] Poison Control Center. “Milkweed Plant Can Cause Serious Poisoning.” https://www.poison.org/articles/milkweed-can-cause-serious-poisoning-204

[4] Lady Bird Johnson Wildflower Center. “Asclepias incarnata – Swamp Milkweed.” https://www.wildflower.org/plants/result.php?id_plant=ASIN