Butterfly milkweed

Asclepias tuberosa L.

light
Sun–part
water
Medium
tall
46 cm
wide
38 cm

Apocynaceae

Also called Butterflyweed, Butterfly weed, Canada root, Chieger flower, Chiggerflower

When it flowers

Not known yet in the tropics: too few flowering observations to read a season from.

Read from iNaturalist photographs of it in flower. A month counts at 50% of the best month's flowering share (smoothed over three months) and 10% of its flowering count, from at least 100 flowering observations in the band.

PetsNC State Extension lists it as toxic to dogs, cats and horses (25 Oct 2026)
PeopleNC State Extension lists it as mildly poisonous (flowers, fruits, leaves, roots, sap, stems) (25 Oct 2026)

If a child, a pet or anyone may have eaten a plant, contact a doctor or vet straight away, or call the National Poisons Information Centre (AIIMS, New Delhi) on 1800 116 117, free and open 24 hours.

Something wrong with it?

About it

Grows as
PerennialKew's checklist, not yet checked
Climate
TemperateKew's checklist, not yet checked
Wild in
SE. Canada to N. MexicoKew's checklist, not yet checked
Light
Full sun to part shade (3 h or more)Read from NC State Extension, one source
Height
30 cm to 61 cmRead from NC State Extension, one source
Spread
30 cm to 46 cmRead from NC State Extension, one source
Water
Average: moist, well drainedRead from NC State Extension, one source
Flowers
Yellow, orange, redRead from NC State Extension, one source
Coldest it survives
-40 °C (USDA zone 3a)Read from NC State Extension, one source

Not known yet: heat, hottest it survives.

In other languages (12)

Spanish
Algodoncillo inmortal, inmortal
root
ASCTUB, tvffo em ohliketv
French
asclépiade tubéreuse
Estonian
mugul-askleepias
Czech
klejicha hlíznatá
Russian
Ваточник клубненосный
Japanese
ヤナギトウワタ
Danish
orange silkeplante
Dutch
Knolzijdeplant
German
Knollige Seidenpflanze
Polish
Trojeść bulwiasta
Hungarian
Gumós Selyemkóró

Where this comes from

A fact “checked by a majority of its sources” was settled by a vote of the pages it was read from, not by a person reading it; one marked “one source” rests on that page alone. Anything else not marked checked has not been checked yet. Where nothing is known, the page says so rather than guess.