Long-lived Butterfly Weed at Chanticleer Gardens in Wayne, PA

Milkweed (Asclepias tuberosa), aka butterfly weed, is a tuberous rooted perennial native in the Eastern and southern U.S. (USDA hardiness zones 3 to 9). It grows in dry/rocky open woodlands, prairies, farm fields, and along roadsides. Individual plants typically grow as a clump to 1- 3 feet high and 1 ½ feet wide. Unlike many of the other milkweeds (Asclepias spp.), the sap is not milky.

For almost six weeks, from late spring into summer, clusters of vibrant orange to yellow-orange flowers (umbels) cover the plant canopy. The narrow, lance-shaped leaves are attached to hairy stems. Flowers are an important nectar source for many butterfly species and leaves are a key food source for the caterpillars (larvae) of monarch butterflies.

Butterfly weed freely self-seeds in the landscape. Prominent 3 – 6 inch long spindle-shaped seed pods break open when ripe and release multitudes of silky-tailed seeds which may carry a long way by wind. Seed pods may be utilized in dried flower arrangements.

Butterfly weed is a prairie survivor. It grows in average, dry to medium, well-drained soils in full sun. It does well in poor, dry soils, and established plants are highly drought tolerant. Shoots emerge late in the spring and grow rapidly. It frequently included in butterfly gardens, meadows, prairies, or other plantings.

Plants are easily started from seed, but may take 2 – 3 years before flowering. Do not try to dig up plants in the wild as they rarely survive transplanting due to their deep taproot system. Seedlings are best left undisturbed once established, usually after two years.

Few disease and insect problems trouble butterfly weed if grown in the right location. Wet, poorly-drained soil leads to rot rots. Leaves are susceptible to rust and leaf spots, particularly if the ground is overplanted. Pesticide use is rarely warranted. In medical circles the plant is commonly called “pleurisy root”, once used to treat lung inflammations.

Their bright orange flower clusters are among our showiest native wildflowers and picked for floral arrangements.