Nodding Milkweed
Asclepias glaucescens Kunth
A stout borderland milkweed with thick blue-gray leaves and heavy nodding clusters of greenish-white flowers, growing in oak woodland and canyon grassland in the Arizona and New Mexico sky islands.
Also called Glaucous Milkweed.
- Height
- 1 ft–3 ft
- Spread
- 1 ft–2 ft
- Flowers
- green, white
- Bloom
- June to September
- Light
- Part shade, Full sun
- Soil moisture
- Dry, Average
- USDA zones
- 6–10
- Leaves
- Opposite, ovate
- Sap
- Milky latex
- Roots
- Deep taproot, resents transplanting
- Stratification
- 30 days cold-moist
- Range
- 2 states
When it flowers
Nodding Milkweed blooms June to September, peaking in July and August.
How to identify it
- Thick, waxy, distinctly blue-gray (glaucous) leaves.
- Flower clusters nod downward on stout stalks.
- Sturdier and broader-leaved than the other borderland species.
Ecology and wildlife value
A monsoon-season host that provides substantial leaf area at a time when the desert below is exhausted.
Growing nodding milkweed
Rarely offered; needs sharp drainage and summer moisture.
Seed needs about 30 days of cold-moist stratification. Deep taproot, resents transplanting. See how to plant milkweed seed for the full method.
Cautions
Standard milkweed cautions. More on milkweed toxicity.
Where nodding milkweed grows
Recorded in 2 states: Arizona, New Mexico.
Distribution is generalized to state level. For county-level maps see USDA PLANTS and BONAP.
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 94322-1. Royal Botanic Gardens, Kew. Accepted name, authorship and global distribution.
- GBIF 3170302. Global Biodiversity Information Facility. Aggregated occurrence records.
- iNaturalist 158740. Community observations, photographs and phenology.
- 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). Nodding Milkweed (Asclepias glaucescens). Retrieved DATE, from https://milkweedusa.com/species/nodding-milkweed/
"Nodding Milkweed (Asclepias glaucescens)." Milkweed USA, 2026, https://milkweedusa.com/species/nodding-milkweed/. Accessed DATE.
Milkweed USA. "Nodding Milkweed (Asclepias glaucescens)." Last modified 2026-08-01. Accessed DATE. https://milkweedusa.com/species/nodding-milkweed/.
@misc{milkweedusa_speciesnoddingmilkweed,
title = {Nodding Milkweed (Asclepias glaucescens)},
author = {{Milkweed USA}},
year = {2026},
url = {https://milkweedusa.com/species/nodding-milkweed/},
note = {Accessed DATE}
}