James H. Schutte
Family
Asclepiadaceae
Botanical Name
Asclepias
Plant Common Name
Asclepias
General Description
There are about 120 milkweeds in the genus Asclepias. They are generally herbaceous perennials that may be hardy or tender. Species are widely distributed throughout North and South America with a few found in Africa. Asclepias was named by Carl Von Linnaeus for the Greek god of healing, Asclepius, because many of the plants have medicinal properties.
Milkweeds tend to have upright or bushy habits and simple, smooth-edged leaves in various shades of green. Leaf arrangement is variable; some species have alternate leaves while others have leaves found in opposite pairs arranged spirally around the stem or whorled in groups. White, milky, latex sap will ooze from the damaged stems or leaves of many species, but not all. Milkweed sap may also irritate the skin.
Asclepias flowers are borne in clusters at the ends of the stems. The individual blooms are very complex. Each opens to show upright petal structures that form a crown. The pollen is encased in unusual bundles that become attached to the legs of pollinating insects, such as butterflies, bees and wasps, and carried to other such milkweed flowers. Pod-like fruits (follicles) follow. These are upright, bulbous and filled with masses of seeds, each decorated with a plume of silky white hairs. When the mature, dry fruits split open the seed plumes get caught in the wind and the seeds float away.
Most Asclepias grow best in full to partial sun. Soil preference varies widely from species to species. Some favor swamps while others thrive in dry meadows. Hardiness is also highly variable. Many species have substantial taproots, so they are sensitive to disturbance and better grown from seed rather than transplanted. These adaptable, desirable garden flowers are great for sunny beds, wildflower or butterfly gardens. The dried pods of some are also attractive and may be used in everlasting flower arrangements.
