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Asclepias asperula
Also called Antelope Horns, Antelopehorn Milkweed, Immortal, Antelope Horns Milkweed, Spider Antelope Horns
Spider milkweed (Asclepias asperula) is a clump-forming perennial milkweed from the southwestern US and northern Mexico, growing 0.3–0.9 m tall with greenish-yellow flowers. It is a key host plant for monarch caterpillars and needs fast-draining soil and a deep pot or taproot room.
Asclepias asperula, commonly called antelope horns milkweed or spider milkweed, is a species of milkweed native to the Southwestern United States and northern Mexico.
The plant is difficult to cultivate and does not grow well in containers. In cultivation, this species favors quickly draining soil that is high in inorganic matter, such as sand and rock chips. It can grow in loam and clay, if provided with adequate drainage and frequent dryness. Moisture level demands and tolerance depend upon the subspecies and possibly ecotype. The plant has a deep taproot, so it needs to have the deepest-possible pot if grown in a container and should not be waterlogged.
Like several other species of milkweed, A. asperula is a food for monarch butterfly caterpillars. It is one of the most important host plants in the southern United States for the generation of monarch butterflies that develop from eggs that monarchs have laid after spending the winter in Mexico.
Cartwheels · Whitestem milkweed · California milkweed · Heartleaf milkweed · Bloodflower · Curtiss' milkweed · Woollypod milkweed · Desert milkweed · Poke milkweed · Mexican whorled milkweed · Florida milkweed · Swamp milkweed
Text excerpted from the Wikipedia article Asclepias asperula by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.
The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.
Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.
