Butterfly weed
Asclepias tuberosa · Apocynaceae
The gardener's calendar
Ideal time to plant butterfly weed: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Foliage
- Deciduous
- Blooming
- June to September, bright orange flowers
- Adult size
- 16 to 32 inches tall
- Growth
- Moderate
- Hardiness
- Hardy down to -4°F
- Origin
- North America
- Soil type
- Well-drained, light, rather dry
Care
Light
Tuberous milkweed thrives in full sun, with at least 6 hours of direct light daily. It tolerates partial shade but will flower less abundantly. Plant it in a bright location to get the most beautiful orange blooms.
Watering
Water regularly during the first year to establish the root system. Once well established, the plant is very drought tolerant. Reduce watering in summer and fall. Avoid excessive moisture which promotes rot.
Soil
Tuberous milkweed prefers well-drained, light, even poor soil. It adapts well to sandy or gravelly terrain. Improve drainage in compact or clay soil by adding sand or gravel.
Fertilizing
A very light application of balanced fertilizer in spring is more than sufficient. An overfed plant will produce more foliage at the expense of flowers. This species is not demanding and thrives in poor soil.
Pruning
Deadhead spent flowers to extend blooming. In late fall or early spring, cut back dead stems. The plant naturally regrows from the base each year and doesn't require strict pruning.
Diseases and pests
Tuberous milkweed is very disease resistant. Watch for overwatering which can cause root rot. Aphids may appear but often disappear naturally with beneficial insects.
Did you know?
Tuberous milkweed is an essential host plant for monarch butterflies: its larvae feed exclusively on it and accumulate its toxic alkaloids to protect themselves from predators. This biological relationship has fascinated botanists and nature lovers for centuries.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
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Tips generated and checked by Viridia — adapt them to your local climate.