Global menu

The Green pages

Swamp milkweed

English
  • Native Plants,
  • Annuals, perennials and bulbs
Asclepias incarnata
Photo: Jardin botanique de Montréal (Stéphane Bailleul)
Asclepias incarnata

Onglets

Botany

Origin and description

To be cultivated to attract butterflies, especially the monarch (Danaus plexippus plexippus). The monarch caterpillar feeds exclusively on milkweed leaves. Its fragrant flowers, grouped together in umbels, are red or purple-pink. It seems more delicate than the common milkweed (A. syriaca), with its narrower tapered leaves and its longer smooth follicles. Moreover, it doesn’t occupy the same habitat as the common milkweed. The swamp milkweed is a wetland species, found in marshes, ditches and on the banks of rivers, streams and lakes.

Swamp milkweed populations are often scattered, and do not form dense colonies in their natural habitat.

This species is found from central to eastern Canada and the United States.

Height: 60 to 120 cm
Width: 40 to 60 cm
Flowering: red or purple-pink, fragrant, July to August
Attractions for wildlife: attracts butterflies, pollinators and butterflies. Host plant and nectar source for the monarch butterfly.

See also the Québec's native milkweed.

Common name

Swamp milkweed

Latin name (genus)

Asclepias incarnata

English common name

French common name

Botanical family

  • Apocynaceae
Horticulture

Growing conditions

Exposure: sun, semi-shade
Soil type: prefers cool or moist soil, but can tolerate slightly drier conditions
Observation: is not invasive

Hardiness

  • Zone 3

See also

Pests and diseases
Physiological disorders