Individual flower of Showy Milkweed

Milkweed does not normally grow in Calgary, though we have seen a plant or two growing in the wild at either one or possibly two locations in the city. My photo was taken in the garden of friends on 27 July 2014. I love Showy Milkweed - the buds, the opened flowers and the seed pods. This macro shot shows how attractive the very small, individual flowers are - they grow in large clusters to form a flower head (previously posted photo in a comment box below).

"Pollination in this genus is accomplished in an unusual manner, as the pollen is grouped into complex structures called pollinia (or "pollen sacs"), rather than being individual grains, as is typical for plant pollen. The flower petals are smooth and rigid, and the feet of visiting insects (predominantly large wasps, such as spider wasps, which visit the plants for nectar) slip into notches in the flowers, where the sticky bases of the pollinia attach to the feet, pulling the pollen sacs free when the pollinator flies off. Bees, including honey bees only gather nectar from milkweed flowers, and are generally not effective pollinators despite the frequency of visitation.

Species in the Asclepias genus grow their seeds in pods. These seed pods contain soft filaments known as either silk or floss. The filaments are attached to individual seeds. When the seed pod ripens, the seeds are blown by the wind, each carried by several filaments.

Native Americans used fiber in the stems for rope, basketry, and nets. Some Native Americans believed the milky sap had medicinal qualities. However, most species of milkweed are toxic." From Wikipedia.

en.wikipedia.org/wiki/Asclepias_speciosa