Butterfly Weed care — light, water, toxicity and hardiness

Butterfly Weed (Asclepias tuberosa) wants full sun and a drink about every 10 days once established. It is hardy in USDA zones 3 to 9. It is toxic to pets — worth keeping out of reach.

Care facts
scientific nameAsclepias tuberosa
familyApocynaceae
categoryflower
plant typeperennial
lightfull sun
water cadence days10
mature height cm60
min zone3
max zone9
frost toleranttrue
toxic to petstrue
toxic to humanstrue
ediblefalse

How often should I water Butterfly Weed?

Monarch host; deep taproot, never move it.

Is Butterfly Weed toxic?

Cardiac glycosides.

Who eats it

Palatable to browsing animals such as deer: low. Palatable to grazing animals: low. Palatable to people: no.

What it needs

Its shade tolerance is high. Its moisture use is low. Its drought tolerance is high. It wants at least about 28 inches of rain a year. Above roughly 45 inches of annual rain it struggles. It tolerates soil down to pH 4.8. It tolerates soil up to pH 6.8. Its fertility requirement is low. Adapted to coarse, sandy soils: yes. Adapted to medium, loamy soils: yes. Adapted to fine, clay soils: no. It needs at least 135 frost-free days. Its tolerance of chalky soil is medium. Its fire tolerance is high. Fire resistant: no. It has been recorded down to -33°F. It suppresses neighbours chemically: no.

How it grows

It grows as a multiple stem form. Its growth rate is slow. Its lifespan is moderate. It puts on most of its growth in spring and summer. It spreads by seed at a slow rate. It resprouts after damage: no. Coppices: no. At maturity it reaches about 2.0 feet. Its roots go down at least 16 inches. Its shape is erect. It holds its leaves through winter: no.

What it looks like

It blooms in mid summer. The flowers are orange. Conspicuous in flower: yes. The foliage is green. The foliage texture is coarse. In summer the canopy is moderate in porosity. In winter it is porous in porosity. Fall colour: no. The fruit or seed is brown. Fruit begins in summer. Fruit finishes by fall. It fruits medium. The fruit persists on the plant: no. The fruit is conspicuous: yes.

Growing more of it

Propagated by seed: yes. Propagated by cuttings: no. Propagated by container: yes. Propagated by bare root: no. Propagated by bulb: no. Propagated by corm: no. Propagated by tubers: no. Cold stratification required: no. Seedling vigour is low. Commercial availability: routinely available.

Source: Drafted from US Cooperative Extension horticulture guidance; pending HUMAN-05 review (issue 280) · ASPCA Toxic and Non-Toxic Plant List · 2026-09-02