Guide
Choosing Milkweed for Monarchs: Native vs Tropical
The short answer
Not all milkweed is equal for monarchs. The leading recommendation from monarch-conservation groups is to plant native Asclepias species that monarchs co-evolved with, and to avoid non-native tropical milkweed (Asclepias curassavica). Though monarchs will feed on tropical milkweed, it can escape cultivation, spread into natural areas, and disrupt normal migration.
Research found that migrating monarchs at sites with tropical milkweed showed reproductive activity and lingered for weeks, unlike monarchs at sites without it. So choose species native to your region — for example showy milkweed (A. speciosa) and narrowleaf milkweed (A. fascicularis) in the West — to support monarchs without the ecological downsides.
Why native, not tropical
- Tropical milkweed (A. curassavica) is non-native; it can escape and spread into natural areas.
- Monarchs at tropical-milkweed sites stayed and bred instead of migrating normally.
- Conservation groups recommend planting only native milkweed species.
Choosing native species
Pick milkweed native to your region so it fits local conditions and the monarch's natural cycle. Widely available Western natives include showy milkweed (Asclepias speciosa) and narrowleaf milkweed (A. fascicularis); many other species are native to other regions.
✔ Match milkweed to your region's native species list rather than buying whatever is on the shelf.
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- National Wildlife Federation — Twelve Native Milkweeds for Monarchs — Recommend native milkweed monarchs co-evolved with; leading conservation groups now recommend planting only native species
- NIH/PMC — Exposure to Non-Native Tropical Milkweed Promotes Reproductive Development in Migratory Monarchs — Monarchs at sites with tropical milkweed showed reproductive activity and remained for weeks vs those without it