Butterfly weed is a low-maintenance plant that does not require any additional fertilization—in fact, doing so can harm the plant, making it excessively leggy and reducing blooms.
It's important to get your watering cadence right for the plant. It should be watered regularly until new growth starts to appear (this includes leaves and stems, not just blooms), at which point you can decrease the frequency with which you water. Additionally, butterfly weed plants should not be fertilized. While fertilizer may work to make other plants bloom, it can actually harm butterfly weed and discourage blooming.
These are very similar plants and members of the same plant genus. Both are of great value to butterflies and other pollinators. But butterfly weed has notable orange flowers, while milkweed has white or pink/mauve flowers. Further, milkweed is notably toxic, with the potential for fatality if large quantities are consumed by humans or animals. Butterfly weed, on the other hand, has rather mild toxicity, and fatalities are very rare.
Butterfly weed is very attractive to feeding rabbits. Rodent repellant granules or sprays can provide some prevention, but metal fencing around the plants is the best solution.
Common Pests and Plant Diseases
Other than the root rot that can appear in dense, wet soils, there are only a couple of common problems with butterfly weed.
Butterfly weed is commonly planted in formal garden borders and in meadow and prairie gardens. This wildflower does not transplant well as it has a deep woody taproot. It is easily propagated from seed. Collect the seed from the pods has they just begin to open. Butterfly weed seed need a three-month cold stratification. Therefore, it is best to plant the seed in autumn and they will easily germinate the following spring.
Butterfly weed grows commonly in dry open habitats and is very common in the prairies and grasslands of the Midwest and Great Plains. This beautiful native wildflower is found from Maine to South Dakota to the desert southwest to Florida.
Asclepias tuberosa range map. USDA PLANTS Database.
Butterfly Milkweed (Asclepias tuberosa L.)
Butterfly weed is a member of the milkweed family (Asclepiadaceae). The genus name Asclepias is named after the Greek god of medicine Asklepios. The species name tuberose refers to the tuberous (knobby and with swellings) roots.
Butterfly milkweed (Asclepias tuberosa). Photo by Larry Stritch.
Butterfly milkweed (Asclepias tuberosa). Photo by Daniel Reed, courtesy of the University of Tennessee Herbarium.
For More Information
Butterfly weed is a coarse perennial forb consisting of many stems. The stems are straight and very hairy. The leaves are alternate and simple. Unlike other species of milkweed butterfly weed does not contain the characteristic thick milky sap but instead has a watery translucent sap. The inflorescence is slightly rounded to flat and made up many individual flowers. The flower consists of five petals pointing down and topped by a crown of five erect hoods. The fruit is a pod containing numerous brown seed each with a tuft of silky white hairs. Many a child and adult have gleefully pulled the seeds from a ripened, opened pod and let them float gracefully on a gentle breeze.
Butterfly milkweed (Asclepias tuberosa). Photo by T.G. Barnes.