Butterfly weed (Asclepius tuberosa) is a type of milkweed plant known for attracting butterflies to its flowers. The plant goes by the name of orange milkweed, chigger flower and pleurisy root, according to the "National Audubon Field Guide to Wildflowers." Planting butterfly weed in your garden setting or on your property can lure a variety of butterflies into viewing range as they seek its nectar. Butterfly weed belongs to the milkweed family and shares many, but not all, of the characteristics of that genus.
Butterfly weed is shorter than many other types of milkweed, standing around 2 to 3 feet tall. The plant flowers from June through September, producing orange to red blooms in clusters at the top of its stems. The flowers are around three-eighths of an inch wide and grow in clusters 2 inches in diameter. The flowers possess five petals. The narrow oblong leaves are between 2 and 6 inches in length and grow in an alternate pattern up the stems. The flowers morph into 4 to 5 inch long green seedpods that eventually open up and release the tiny seeds, which blow away in the breeze with the aid of a small tuft of hair that serves as a sort of sail.
One of butterfly weed's best qualities is that it will return every year and be of very little trouble in your garden. Plant this milkweed in full sun but remember that if need be, it can withstand partial shade and still flourish. In the wild, the plant grows in open meadows and fields east of the Rockies in North America. Sandy soil that drains fairly well will support butterfly weed and the plant is drought-hardy. If planting new specimens, the Floridata website recommends taking careful note of where you placed them, since they do take a while to begin growing in the spring.
Developing butterfly weed from its seeds is possible but requires a certain protocol to work effectively. Gather the seeds after the seedpods open up or are about ready to burst. Since the seeds need exposure to the cold to germinate, you should plant them in the fall. Your other option is to place the seeds in your freezer for some weeks before planting them in the spring.
The familiar black and orange monarch butterfly lays its eggs exclusively on milkweed and the insect will use butterfly weed for this purpose in many cases. However, when it has a choice, the monarch will prefer other species of milkweed for this purpose. All milkweeds contain toxins that the developing monarch caterpillars can absorb into their system with no ill effects from feeding on the plant, making them poisonous if eaten by predators. Butterfly weed is much lower in these toxins, states the Butterfly Gardening and Conservation Center website. The caterpillars feeding on it are not as much of a threat to the health of something that eats them, making them a potential meal.
Butterfly weed is an odd milkweed in that its sap is clear rather than milky, which is far from the norm for this genus. Most milkweeds will have leaves growing opposite each other in pairs, another feature in which the butterfly weed differs from its relatives. Native Americans found that digging up the roots of butterfly weed and chewing it helped alleviate respiratory congestion; this led to the plant's nickname as pleurisy root.