Native to South Africa, but distributed widely around the world as an ornamental plant. As a milkweed it also serves as a foodplant for milkweed butterflies, such as The Monarch. A common roadside weed in Hawaii.
A perennial that reproduces from seeds. Grows commonly along dry or wet areas of roadsides and in cultivated areas, forming large stands of semi-woody plants up to 5 feet tall. Plants will have multiple seed pods, each containing about 200 seeds that may be scattered by the wind, carried by long silky hairs.
Mature plants are from 2 to 5 feet in height on strong stems that branch from a main stem. Leaves are opposite along the stems and linear in shape, being narrow and elongated. White flowers form as clusters at the ends of terminal stems. The fruit or seed pod is large and conspicuous, 2 to 4 inches long, football shaped, and covered with rows of short spiny hairs.
Characteristicts Important to Control:
As a perennial weed it is necessary to kill the roots to control it, requiring a systemic product that will carry to the roots. Pre-emergent control may be possible, but seeds will be carried long distances from the parent plant with wind movement. It is often used as a desirable ornamental or as a food plant for butterflies.