Narrowleaf Milkweed
Asclepias fascicularis
Last reviewed: June 2026
Asclepias fascicularis is a drought-tolerant native milkweed found across the western United States that blooms from May through September. This perennial forb attracts butterflies, bees, and moths while thriving in full sun conditions.
Narrowleaf Milkweed is toxic to dogs and cats.
Listed as toxic by the ASPCA Animal Poison Control Center (opens in new tab) (last reviewed 2026-06-03). If your pet has been exposed, call the ASPCA Animal Poison Control Center at (888) 426-4435and your veterinarian's emergency line.
Pollinator Patch flags toxic plants so you can choose a pet-safe native alternative for your yard.
Light
full sun
Water
low
Size
24"–36" H × 12"–24" W
Bloom
May, Jun, Jul, Aug, Sep
Native to
AZ, CA, ID, NV and 3 more states
Pollinators
butterflies, bees, moths
Browse plants for this ecoregion
Narrowleaf Milkweed produces clusters of small white to pale pink flowers from late spring through fall on upright stems with narrow, linear leaves. This drought-tolerant perennial grows in a compact clump and goes dormant in winter, dying back to the ground before returning in spring.
Growing Narrowleaf Milkweed
Grow Narrowleaf Milkweed in full sun and low water. Mature plants reach 24 to 36 inches tall and spread 12 to 24 inches wide. Expect moderate maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Narrowleaf Milkweed is an HOA-friendly choice in the right placement. Maintenance level: moderate. Tidiness: 2 out of 5.
Works well in: front yard, mid zone, street edge.
- Goes dormant and dies back in winter
- Can self-seed in irrigated beds
Wildlife value
Host plant for monarch butterfly, queen butterfly.
Essential host plant for monarch butterfly caterpillars and provides nectar for many butterflies, bees, and moths. The flowers are particularly attractive to migrating monarchs during their fall journey.
Common questions
- Where is Narrowleaf Milkweed native to?
- Asclepias fascicularis is native to seven western states: Arizona, California, Idaho, Nevada, Oregon, Utah, and Washington.
- When does Narrowleaf Milkweed bloom?
- Narrowleaf Milkweed typically blooms from May through September, providing nectar for pollinators across the growing season.
- What pollinators visit Asclepias fascicularis?
- This milkweed species attracts butterflies, bees, and moths, making it valuable for supporting diverse pollinator communities.
- What growing conditions does Narrowleaf Milkweed prefer?
- Asclepias fascicularis thrives in full sun locations with low water requirements, making it well-suited for drought-tolerant gardens and natural landscapes.
- Is Narrowleaf Milkweed toxic to dogs?
- Yes. Narrowleaf Milkweed is listed as toxic to dogs by the ASPCA Animal Poison Control Center (aspca.org). If your pet has been exposed, call the ASPCA Animal Poison Control Center at (888) 426-4435.
- Is Narrowleaf Milkweed toxic to cats?
- Yes. Narrowleaf Milkweed is listed as toxic to cats by the ASPCA Animal Poison Control Center (aspca.org). If your cat has been exposed, call the ASPCA Animal Poison Control Center at (888) 426-4435.
- Is Narrowleaf Milkweed HOA-friendly?
- Narrowleaf Milkweed is generally an HOA-friendly choice in the right placement, with moderate maintenance.
Native range data from the USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Pollinator Patch flags toxic plants like Narrowleaf Milkweed and shows pet-safe natives for your ecoregion instead.