green comet milkweed

Asclepias viridiflora

Summary 5

Asclepias viridiflora, common names green milkweed, green comet milkweed, and green-flower milkweed is a widely distributed species of milkweed known from much of the eastern and central United States from Connecticut to Georgia to Arizona to Montana, as well as southern Canada.

Comments 6

This non-showy plant is unlikely to receive favor from the mass market in horticulture, but it is nonetheless quite interesting to examine. This milkweed species is rather variable across different localities; there is a variety with narrow leaves that occurs in sandy areas near Lake Michigan. Short Green Milkweed (Asclepias viridiflora) can be distinguished from many species of milkweeds by its nodding umbels of greenish flowers. The rare Mead's Milkweed (Asclepias meadii) has this characteristic, but its flowers are more wide (about 6 mm. across) and the hoods of its flowers have horns. Another milkweed species, Tall Green Milkweed (Asclepias hirtella), produces nodding umbels of greenish flowers, but its umbels are more fully globoid in shape, and its leaves are usually more linear and narrow than those of Short Green Milkweed.

Description 7

This perennial plant is 1½–2' tall and unbranched. The central stem is light green to light purplish green and more or less pubescent. Several pairs of opposite leaves occur along the entire length of the stem; they are more or less ascending. The leaves are often folded upward along their margins, where they are often wavy (up and down). Individual leaves are up to 5" long and 1½" across; they are linear-lanceolate to lanceolate in shape and smooth (entire) along their margins. The upper leaf surface is medium green, while the lower leaf surface is light green; both surfaces are short-pubescent to nearly glabrous. The petioles are about 3 mm. (1/8") long, light green to light reddish green, and pubescent. The primary veins of the leaves are pinnate, while their secondary veins form a reticulated network that is visible on their undersides. From the axils of middle to upper leaves, there are nodding umbels of flowers spanning 1–1¾" across (only one umbel per pair of leaves). These umbels have short pubescent peduncles up to 6 mm. (¼") long. A typical plant will have 1-4 umbels; each umbel has 15-45 flowers on hairy pedicels about ½" long. Individual umbels are broadly obconic to half-globoid in shape and dome-shaped in front, rather than flat-headed. Each flower is about 8 mm. long and 3 mm. across, consisting of 5 erect hoods, 5 deflexed petals, 5 deflexed sepals, and the reproductive organs. The flowers are light green to green, becoming yellowish green or purplish green as they age. Individual hoods are lanceolate-oblong in shape; they are without horns. The hoods surround a central reproductive column on all sides; this column contains masses of winged pollinia (packets of pollen). The deflexed petals are lanceolate in shape; when the flower is fully open, they hide the shorter sepals. The sepals are linear-lanceolate in shape, light green to purplish green, and hairy. The blooming period occurs during early summer, lasting about 3 weeks. Afterwards, the flowers that have been cross-pollinated successfully (if any) are replaced by follicles (seedpods that open along one side). The follicles are up to 3½–5" long and ½–¾" across; they are narrowly lanceoloid and usually short-pubescent. During the autumn, these follicles split open to release their seeds. The seeds are dark brown, flattened-ovoid in shape, and winged along their margins. At their apices, the seeds have tufts of white hair; they are distributed by the wind. The root system consists of a central taproot. This plant usually occurs as scattered individuals, rarely forming colonies. Cultivation

Sources and Credits

  1. (c) Jenny Smith, some rights reserved (CC BY-NC), uploaded by Jenny Smith
  2. (c) Peter Gorman, some rights reserved (CC BY-NC-SA), https://www.flickr.com/photos/52421717@N00/3690183939/
  3. (c) Aaron Lincoln, some rights reserved (CC BY-NC), uploaded by Aaron Lincoln
  4. (c) Carolyn Gritzmaker, some rights reserved (CC BY-NC), uploaded by Carolyn Gritzmaker
  5. Adapted by Amber Leung from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Asclepias_viridiflora
  6. (c) John Hilty, some rights reserved (CC BY-NC), http://eol.org/data_objects/29441460
  7. (c) John Hilty, some rights reserved (CC BY-NC), http://eol.org/data_objects/29441457

More Info

iNat Map

Family Apocynaceae