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Swamp milkweed

Swamp milkweed has delicate rosy pink flowers.

Swamp milkweed is an erect, clump-forming, native plant commonly found in wet meadows and along riverbottoms.  An essential plant for the rain garden.  The rosy pink flowers are a prime source of nectar for many butterflies.


Botanical name:

Asclepias incarnata

All common names:

Swamp milkweed

Family (English):

Dogbane (formerly milkweed)

Family (Botanic):

Apocynaceae (formerly Asclepiadaceae)

Tree or Plant Type:

  • Perennial


  • Deciduous (seasonally loses leaves)

Native Locale:

  • Chicago area,
  • Illinois,
  • North America

Landscape Uses:

  • Foundation,
  • Massing,
  • Mixed border

Size Range:

  • Large plant (more than 24 inches)

Light Exposure:

  • Full sun (6 hrs direct light daily)

Hardiness Zones:

  • Zone 3,
  • Zone 4,
  • Zone 5 (Chicago),
  • Zone 6

Soil Preference:

  • Moist, well-drained soil,
  • Wet soil


  • Wet sites,
  • Occasional flooding,
  • Clay soil

Seasons of Interest:

  • midsummer,
  • late summer

Flower Color & Fragrance:

  • Fragrant,
  • Pink

Shape or Form:

  • Upright

Growth Rate:

  • Slow

More Information:


2 to 5 feet high and 2 to 3 feet wide

Tree & Plant Care

Requires full sun in moist to wet soil, can tolerate well drained soils.
Foliage is slow to emerge in spring.
Plants have deep taproots and difficult to transplant.

Disease, pests and problems

Milkweed bugs and milkweed beetle are late season pests.

Disease, pest and problem resistance

Deer, rabbit

Native geographic location and habitat

C-Value: 4
Commonly found in swampy areas and wet meadows.

Attracts birds & butterflies

Small rosy-pink flowers is a great nectar source for many butterflies and leaves are the larval host for the monarch butterfly.

Leaf or needle arrangement, size, shape, and texture

Opposite,  3 to 6 inches long, lance shaped with pointed tips

Flower arrangement, shape, and size

Small, fragrant, pink to mauve flowers (1/4 inch wide),  with five reflexed petals in a loose umbels at the stem ends in summer.
Said to smell like vanilla scent.

Fruit, cone, nut, and seed descriptions

 Long, 4  to 5 inch green seed pods (follicles) split and release light to dark brown seeds attached to silver-white silky hairs. 

Location of Asclepias incarnata (Swamp milkweed) at the Arboretum