How to Grow Butterfly Weed in Your Garden

What is a butterfly weed? Butterfly weed plants (Asclepias tuberosa) are trouble-free North American natives that produce umbels of bright orange, yellow, or red blooms all summer long. Butterfly weed is appropriately named, as the nectar and pollen rich flowers attract hummingbirds and hordes of butterflies, bees, and other beneficial insects throughout the blooming season. Do you want to know more about how to grow butterfly weed?

This Arkansas native is what folks think of when they are considering adding butterfly weed into their gardens. Sporting brilliant orange flowers, it will look wonderful in any color arrangement. How do you grow butterfly weed successfully? Growing in a clump 12”-36” tall, they want very good drainage in a full sun situation if you have it. If you do not have a full sun spot, ½ day sun preferably in the afternoon will also work. Quite drought tolerant once established. Flowers are a nectar source for many butterflies and the leaves are a food source for Monarch butterfly larvae. Asclepias tuberosa blooms from late spring through summer. Fertilize with an organic, slow release fertilizer in the spring, once new growth has begun.

Where, When and How to Plant

Butterfly weed is hardy through New England. Sow seeds indoors in peat pots 6 to 8 weeks before your last frost date, thinning to one plant per pot. Or plant locally purchased plants in spring after danger of frost has passed or summer, in full sun on compost-amended, well-drained soil. Poor soil drainage is the one thing butterfly weed won’t stand. Space plants 2 to 3 feet apart. Butterfly weed has a taproot, so once planted it’s difficult to move.

Growing Tips

The good news is that milkweeds have a long, deep taproot that helps them be drought tolerant. The bad news is: this can make them a bit tricky to transplant and relocate. Try to find their “forever” home to avoid moving them, but if needed try to get as much of the root ball as you can. If you let the seed pods dry out and open, there is a good chance the seeds might self-sow and sprout, giving you more plants. Expect to wait a few years after the seeds germinate to get flowers.

Regional Advice and Care

Deadhead spent flowers to encourage more flowering and reduce self-sowing. Weed out self-sown seedling each spring. Be carefully when pruning the plant as the stems have a milky sap that might be irritating to your skin. Cutback the plant to the ground in fall after a frost and compost it. It needs little care once established in the garden and can be drought tolerant. Aphids can sometimes be a problem and are easily controlled with sprays of insecticidal soap. Butterfly weed plants can withstand damage from the Monarch butterfly caterpillars. Don’t spray to kill them or you’ll not have any beautiful butterflies.

Other Perennial Milkweeds

Asclepias tuberosa ‘Hello Yellow’ is very similar to regular butterfly weed, but is a beautiful butter yellow color. Consider growing both colors together for a bright and cheery combination. Planting and growing conditions are the same as for the orange butterfly weed.

Asclepias incarnata is a bit different, in that its nickname says it all—swamp milkweed. This one prefers moist soil and grows 24”-48” tall in full sun. This beauty has small rose pink flowers in a cluster. Breathe easy, because blooms are fragrant!

Asclepias syriaca is another milkweed native to the southeast United States and this one can grow up to six feet tall! This one can spread by underground rhyzomes so either plant it in a space with a lot of room, thin periodically and/or remove seed pods to control growth. In addition to butterflies, this milkweed attracts other pollinators such as honeybees and hummingbird moths. In fact, it’s also called nature’s mega food mart, because over 450 insects known to feed on some part of it.