Rush Milkweed (Asclepias subulata): The Only Evergreen Milkweed Native to the U.S.

Monarchs and queens need milkweed — and the Southwest has its own. Rush milkweed (Asclepias subulata), aka desert milkweed, is the only evergreen milkweed native to the U.S. Upright succulent stems, creamy yellow flowers spring–fall, thrives in full reflected sun with minimal water.

Noelle Johnson Landscape Consulting

Quick Facts

• Botanical name: Asclepias subulata
• Common names: Rush milkweed, desert milkweed
• Origin: Desert SW: AZ, CA, NV, N. Mexico
• Hardiness: 20–25 °F / –7 to –4 °C (Zone 9)
• Water: Low. Established: monthly May–Sept.
• Light: Full sun
• Size: 3–4' tall & wide

Queen butterfly on rush milkweed, Desert Botanical Garden, Phoenix. Noelle Johnson Landscape Consulting

Distinguishing Traits

• Gray-green succulent stems, leafless except brief 2" narrow leaves on new warm-season growth
• Upright habit in full sun = strong vertical element
• Creamy yellow buds → tiny 5-petaled flowers spring, periodic summer/fall
• Larval food for monarch & queen caterpillars; bees, hawk moths, milkweed bugs visit
• Horn-shaped seedpods split to release black seeds on silvery hairs

Noelle Johnson Landscape Consulting

Noelle Johnson Landscape Consulting

Noelle Johnson Landscape Consulting

Design Versatility

• Natural desert: Scattered throughout
• Formal/contemporary: Straight rows
• Companions: Blackfoot daisy, brittlebush, firecracker penstemon
• Hot spots: Raised planters, west-facing walls, walkways
• Succulent pairings: Santa Rita prickly pear, artichoke agave — contrast shapes/textures

In narrow planter, hot reflected sun. Noelle Johnson Landscape Consulting

With artichoke agave & blackfoot daisy in raised planter. Noelle Johnson Landscape Consulting

Planting & Care

Well-drained soil, full/reflected sun. No fertilizer/amendments. Low maintenance: prune leggy/damaged stems to base in late winter. Wear gloves — milky sap irritates skin, toxic if ingested (contains rubber, but not a commercial source).

Queen butterfly on rush milkweed in fall