Overview
The only larval food plant for monarch butterflies, making milkweed conservation a matter of species survival. Common milkweed also has a rich ethnobotanical history — young shoots, flower buds, and immature pods are all edible after proper cooking to remove the bitter latex. The silky floss from seed pods was used to fill life jackets during WWII and is being explored as a modern sustainable insulation material.
Growing Conditions
LightPartial Sun
MoistureModerate
Hardiness Zones5 — 9
Height0.6m
Spread0.6m
Growth HabitForb/herb
Pollinator Valuehigh
Companion Planting & Soil
Good Companions
Soil pH5 — 7.5
Soil TypeAverage, well-drained soil; adaptable to most conditions
Planting Calendar
When to sow, transplant, and harvest by growing zone.
| Zone | Action | Months | Notes |
|---|---|---|---|
| Cold (1-2) | Direct Sow | Oct — Nov | Fall sow outdoors for natural cold stratification; essential monarch host plant |
| Cold (1-2) | Bloom | Jun — Aug | Blooms midsummer; do NOT deadhead — monarch caterpillars need the foliage |
| Cool (3-4) | Direct Sow | Oct — Nov | Fall sow; seeds need 30+ days cold stratification to germinate |
| Cool (3-4) | Bloom | Jun — Aug | Peak bloom midsummer; leave seed pods for self-sowing and winter interest |
| Moderate (5-7) | Direct Sow | Oct — Nov | Fall sow; or cold-stratify seed in fridge 30 days before spring sowing |
| Moderate (5-7) | Transplant | Apr — May | Transplant nursery plants in spring; deep taproot — choose location carefully |
| Moderate (5-7) | Bloom | May — Aug | Blooms late spring through summer; critical pollinator plant |
| Moderate (5-7) | Divide | Mar — Apr | Divide clumps carefully in early spring; disturb taproot as little as possible |
| Warm (8-9) | Transplant | Mar — Apr | Plant tropical milkweed (A. curassavica) or native A. tuberosa |
| Warm (8-9) | Bloom | Apr — Sep | Long bloom season; attracts monarchs, bees, and hummingbirds |
| Hot (10+) | Transplant | Feb — Mar | Plant in spring; tropical milkweed is evergreen — cut back in fall to prevent OE parasite |
| Hot (10+) | Bloom | Mar — Oct | Year-round bloom for tropical species; cut back once annually |
Uses
Culinary
- Young shoots cooked like asparagus (after blanching to remove bitterness)
- Immature flower buds and young pods cooked as vegetables
- Must be properly prepared — do not eat raw
Medicinal
- Latex traditionally used for wart removal (topical)
- Root tincture historically used for respiratory conditions by Native Americans
Other Uses
- Critical monarch butterfly conservation plant
- Seed floss explored as sustainable fiber and insulation
- Native meadow restoration species
Safety Notes
Although no specific reports have been seen for this species, many, if not all, members of this genus contain toxic resinoids, alkaloids and cardiac glycosides[274]. They are usually avoided by grazing animals[274]. This species is said to be poisonous to livestock[228].
