Broadleaf Milkweed
Asclepias latifolia (Torr.) Raf.
Thick, almost circular leaves stacked up a stout stem like a pile of green plates, with flower clusters tucked into the leaf axils. A tough, deeply rooted southern plains species that thrives where summer means 100°F and no rain.
Also called Corn-kernel Milkweed, Broadleaf Milkvine.
- Height
- 1 ft–3 ft
- Spread
- 1.5 ft–4 ft
- Flowers
- green, cream
- Bloom
- May to August
- Light
- Full sun
- Soil moisture
- Dry
- USDA zones
- 5–9
- Leaves
- Opposite, orbicular
- Sap
- Milky latex
- Roots
- Rhizomatous, spreads by root
- Stratification
- 30 days cold-moist
- Range
- 10 states
When it flowers
Broadleaf Milkweed blooms May to August, peaking in June and July.
How to identify it
- Leaves are very broad, blunt-tipped and often wider than they are long, clasping the stem closely.
- Flower clusters sit in the leaf axils rather than crowning the plant.
- Stems are stout and unbranched, giving a stiff, architectural look.
Unfamiliar words are in the glossary, and the identification key will narrow a plant down from what you can see.
The parts that identify it
Ecology and wildlife value
Its big leaves make it a productive monarch host on the southern plains, where it is one of the few milkweeds with real leaf area. Grazing animals avoid it, so it persists on heavily used rangeland.
Monarchs are not the only thing that will find it. Expect large milkweed bugs on ripening pods, oleander aphids on the stems, red milkweed beetles at the flowers and, in late summer, milkweed tussock moths. Everything that lives on milkweed.
Growing broadleaf milkweed
Extremely drought-tolerant and long-lived, but rhizomatous and considered a rangeland weed by ranchers. Rarely offered in the nursery trade.
Seed needs about 30 days of cold-moist stratification. Rhizomatous, spreads by root. See how to plant milkweed seed for the full method.
Cautions
Toxic to livestock, and unpalatable enough that it increases on overgrazed land. More on milkweed toxicity.
Where broadleaf milkweed grows
Recorded in 10 states: Arizona, Colorado, Kansas, Nebraska, New Mexico, Nevada, Oklahoma, Texas, Utah, Wyoming.
County records from USDA PLANTS, public domain. Cross-check against BONAP and your regional flora before making management decisions.
References and further reading
Names, ranges and conservation status here are drawn from the databases below. Where those disagree with a regional flora, trust the flora.
- Plants of the World Online 94386-1. Royal Botanic Gardens, Kew. Accepted name, authorship and global distribution.
- GBIF 3170304. Global Biodiversity Information Facility. Aggregated occurrence records.
- iNaturalist 62296. Community observations, photographs and phenology.
- Wikipedia. General-audience article on this species.
- BONAP county distribution map. Biota of North America Program. County-level range map.
- NatureServe Explorer. Conservation status ranks at global and state level.
- World Flora Online. Nomenclature and synonymy.
- Woodson, R. E. (1954). The North American species of Asclepias L.. Annals of the Missouri Botanical Garden 41(1): 1–211. The monograph the modern taxonomy of the genus still rests on. View
- Flora of North America Editorial Committee (eds.) (2026). Flora of North America North of Mexico. Oxford University Press, New York and Oxford. Accepted names, keys and descriptions for the North American flora. View
- Royal Botanic Gardens, Kew (2026). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Nomenclature and global distribution, keyed to IPNI name identifiers. View
- Kartesz, J. T. (Biota of North America Program) (2026). North American Plant Atlas. BONAP, Chapel Hill, North Carolina. County-level distribution maps, the basis for the ranges generalized here. View
- USDA, NRCS (2026). The PLANTS Database. National Plant Data Team, Greensboro, North Carolina. State-level distribution, wetland status and nomenclature. View
- Agrawal, A. A. (2017). Monarchs and Milkweed: A Migrating Butterfly, a Poisonous Plant, and Their Remarkable Story of Coevolution. Princeton University Press. The standard general account of the milkweed and monarch relationship. View
Cite this page
This page is licensed CC BY 4.0. Quote it, adapt it and reuse it, including commercially, as long as you credit Milkweed USA and link back.
Milkweed USA. (2026). Broadleaf Milkweed (Asclepias latifolia). Retrieved DATE, from https://milkweedusa.com/species/broadleaf-milkweed/
"Broadleaf Milkweed (Asclepias latifolia)." Milkweed USA, 2026, https://milkweedusa.com/species/broadleaf-milkweed/. Accessed DATE.
Milkweed USA. "Broadleaf Milkweed (Asclepias latifolia)." Last modified 2026-08-01. Accessed DATE. https://milkweedusa.com/species/broadleaf-milkweed/.
@misc{milkweedusa_speciesbroadleafmilkweed,
title = {Broadleaf Milkweed (Asclepias latifolia)},
author = {{Milkweed USA}},
year = {2026},
url = {https://milkweedusa.com/species/broadleaf-milkweed/},
note = {Accessed DATE}
}