MilkweedUSA

Native Subspecies of California Milkweed

Greene’s Milkweed

Asclepias californica subsp. greenei Woodson

The northern half of the species, from Kern and San Luis Obispo counties up through the Coast Ranges and the Sierra foothills.

How to tell it apart

Crown segments are shorter, 3 to 4 mm, with a squared-off tip, and split down less than half their length. The crown can be light pink rather than the usual red-violet.

Compare with subsp. californica. Everything else about the plant, including how to grow it and what it is worth to monarchs, is on the california milkweed page.

Where it grows

Takes over from the typical subspecies north of Kern and San Luis Obispo counties, including on serpentine, which the southern plant does not use.

Alaska: not recorded Maine: not recorded Vermont: not recorded New Hampshire: not recorded Washington: not recorded Idaho: not recorded Montana: not recorded North Dakota: not recorded Minnesota: not recorded Illinois: not recorded Wisconsin: not recorded Michigan: not recorded New York: not recorded Massachusetts: not recorded Rhode Island: not recorded Oregon: not recorded Nevada: not recorded Wyoming: not recorded South Dakota: not recorded Iowa: not recorded Indiana: not recorded Ohio: not recorded Pennsylvania: not recorded New Jersey: not recorded Connecticut: not recorded California: recorded Utah: not recorded Colorado: not recorded Nebraska: not recorded Missouri: not recorded Kentucky: not recorded West Virginia: not recorded Virginia: not recorded Maryland: not recorded Delaware: not recorded Arizona: not recorded New Mexico: not recorded Kansas: not recorded Arkansas: not recorded Tennessee: not recorded North Carolina: not recorded South Carolina: not recorded District of Columbia: not recorded Texas: not recorded Oklahoma: not recorded Louisiana: not recorded Mississippi: not recorded Alabama: not recorded Georgia: not recorded Hawaii: not recorded Florida: not recorded
Recorded in 1 state. Shading is generalized to whole states.

Distribution follows the Flora of North America treatment, United States only. California Milkweed as a whole is recorded in 1 states.

Flowering

Greene’s Milkweed blooms March to July, peaking in April and May. Plants reach 1 ft–3 ft.

References

The description, distribution and synonymy here follow Mark Fishbein’s treatment of Asclepias in Flora of North America vol. 14 (2023).

Cite this page

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APA Milkweed USA. (2026). Greene’s Milkweed (Asclepias californica subsp. greenei). Retrieved DATE, from https://milkweedusa.com/species/california-milkweed/greenei/
MLA "Greene’s Milkweed (Asclepias californica subsp. greenei)." Milkweed USA, 2026, https://milkweedusa.com/species/california-milkweed/greenei/. Accessed DATE.
Chicago Milkweed USA. "Greene’s Milkweed (Asclepias californica subsp. greenei)." Last modified 2026-08-01. Accessed DATE. https://milkweedusa.com/species/california-milkweed/greenei/.
BibTeX @misc{milkweedusa_speciescaliforniamilkweedgre, title = {Greene’s Milkweed (Asclepias californica subsp. greenei)}, author = {{Milkweed USA}}, year = {2026}, url = {https://milkweedusa.com/species/california-milkweed/greenei/}, note = {Accessed DATE} }