Showy Milkweed

Asclepias speciosa

Hosts 1 caterpillarSpecialist hostBird foodPollinator plant

Growing it

When	Flowers June to August
Type	wildflower
Sun	Full sun, partial shade
Water	Low
Soil	pH 6–8
Hardiness	zone 3–8
Mature height	1 m
Mature spread	0.75 m
Spacing	0.5 m
Years to maturity	3
Bloom	Jun–Aug
Flower colour	Purple read from a published flora
In bloom	June July August
Native to	AB, SK

elliptic leaves about 15 cm long in opposite pairs

Where it has been recorded

BothSpecimensObservations

119 squares of about 28 km, each holding at least one record. A square is not a claim that the plant grows throughout it, and an unshaded square is unrecorded rather than empty. Darker squares hold more records, which follows roads and towns as much as it follows the plant. 10 herbarium specimens and 356 field observations this project may redraw. A filled dot is a pressed sheet somebody can re-examine; a hollow ring is a photograph identified by community agreement. Where the dots are dense is where people have looked, not where the plant is commonest, and empty ground is unsurveyed rather than unoccupied. How this map is made.

Which ecoregions the records fall in

Moist Mixed Grassland south AB / SK: 443 records, high confidence
Mixed Grassland south AB / SK: 414 records, high confidence
Fescue Grassland south AB: 334 records, high confidence
Aspen Parkland central AB / SK: 21 records, high confidence
Cypress Upland south AB / SK: 14 records, medium confidence

These are counts of records collected somewhere in the region, which is the resolution of the evidence: the map above shows where inside it. A region with 3 records is not the same claim as one with three hundred, so the count travels with the region. A region missing from this list means nobody has recorded it there, which is not the same as the plant being absent. Records within 900 m of a border count for neither side, because the border is not drawn finely enough to say which one they are on. Source: GBIF occurrence search + PRESERVED_SPECIMEN pass, retrieved 2026-08-24. Boundaries digitised from the National Ecological Framework for Canada v2.2 (Ecological Stratification Working Group 1995), simplified to about 900 m for display: an outline is accurate to roughly a kilometre, not to the metre. How these counts are made.

See every observation, live and current, on GBIF or iNaturalist.

Documented animals

59 documented relationships, 1 with a specialist that has no alternative.

nectar for

Alkali Bee Poelen et al. 2014
American Bumble Bee Poelen et al. 2014
American Lady Poelen et al. 2014
Anthophora urbana Poelen et al. 2014
Argynnis idalia Poelen et al. 2014
Bembix amoena Poelen et al. 2014
Brown-belted Bumble Bee Poelen et al. 2014
Brown-tailed Bumble Bee Poelen et al. 2014
Bumblebee-like Digger Bee Poelen et al. 2014
Bumblebees Wilson & Carril 2015
Callophrys affinis Poelen et al. 2014
Canadian Tiger Swallowtail Poelen et al. 2014
Chlosyne gorgone Poelen et al. 2014
Cobalt Milkweed Beetle Poelen et al. 2014
Confusing Bumble Bee Poelen et al. 2014
Convergent Lady Beetle Poelen et al. 2014
Coral Hairstreak Poelen et al. 2014
Ectemnius spiniferus Poelen et al. 2014
Euphydryas colon Poelen et al. 2014
Formica obtusopilosa Poelen et al. 2014
Gnophaela latipennis Poelen et al. 2014
Golden Northern Bumble Bee Poelen et al. 2014
Gray Hairstreak Poelen et al. 2014
Great Spangled Fritillary Poelen et al. 2014
Halictus tripartitus Poelen et al. 2014
Heriades carinata Poelen et al. 2014
Hesperia uncas Poelen et al. 2014
Hunt's Bumble Bee Packer
Hylaeus mesillae Poelen et al. 2014
Indiscriminate Cuckoo Bumble Bee Poelen et al. 2014
Lasioglossum incompletum Poelen et al. 2014
Lasioglossum pruinosum Poelen et al. 2014
Megachile angelarum Poelen et al. 2014
Megachile brevis Poelen et al. 2014
Megachile onobrychidis Poelen et al. 2014
Megachile perihirta Poelen et al. 2014
Megachile texana Poelen et al. 2014
Monarch Acorn & Sheldon 2006
Neophasia menapia Poelen et al. 2014
Neorhynchocephalus sackenii Poelen et al. 2014
Nevada Bumble Bee Poelen et al. 2014
Northern Amber Bumble Bee Poelen et al. 2014
Occidental Digger Bee Poelen et al. 2014
Orange Sulphur Poelen et al. 2014
Orange-banded Bumble Bee Poelen et al. 2014
Orange-legged Furrow Bee Poelen et al. 2014
Osmia calla Poelen et al. 2014
Pale Swallowtail Poelen et al. 2014
Red-belted Bumble Bee Poelen et al. 2014
Ruby-throated Hummingbird Poelen et al. 2014
Satyrium californica Poelen et al. 2014
Satyrium sylvinus Poelen et al. 2014
Silver-spotted Skipper Poelen et al. 2014
Tharsalea dione Poelen et al. 2014
Variegated Fritillary Poelen et al. 2014
Western Tiger Swallowtail Poelen et al. 2014
White-lined Sphinx Poelen et al. 2014

caterpillar host for

Monarch ★Acorn & Sheldon 2006
Ornate Checkered Beetle Poelen et al. 2014

Also worth knowing

Safety

High toxicity to pets; High toxicity to people

Edible parts

Shoots (cooked), flowers

Buying it

About $8–$16 per plant (estimate), usually from a native-plant nursery. Estimate (herb default); AB retail as of 2026

Where these numbers came from

Flower detail: not verified, a genus-level estimate