Butterfly Weed (Asclepias) in Zone 3a & 3b

Asclepias tuberosa

When to plant butterfly weed (asclepias) in zone 3b

Zones 3a and 3b share the same average frost dates in our data, so this page covers both.

Method: Start indoors: Start indoors from seed, then transplant outside. Butterfly Weed (Asclepias) needs a head start most zones can't give it by direct-sowing alone.

Spacing: 1 per square foot (square-foot-gardening spacing). Mature height: 1.5-3 ft.

Butterfly weed is a native perennial wildflower grown as much for feeding monarch butterfly caterpillars, one of the milkweeds they depend on, as for its own clusters of bright orange flowers.

How butterfly weed (asclepias) fits zone 3's season

Zone 3b's frost-free window runs about 98 days, from May 30 to September 5. Butterfly Weed (Asclepias) needs about 365 days from transplant to first harvest.

Good companions

No standout companions recorded yet for Butterfly Weed (Asclepias).

Where to buy butterfly weed seeds

• Botanical Interests
• True Leaf Market
• Burpee
• High Mowing Organic Seeds

See why we recommend these suppliers →

As an Amazon Associate we earn from qualifying purchases. Some links on this page also go to other retailers we may earn a commission from as an affiliate, at no extra cost to you. We only recommend products with a genuine consensus of positive, independent reviews. See the sources cited on each item.

See it growing

Search YouTube for "growing butterfly weed (asclepias)" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)

← Back to the full zone 3b calendar · Full companion planting guide · Full plant profile · Plan your beds in the Garden Designer →

Pin this for later

Growing Butterfly Weed (Asclepias) in USDA zone 3b: when to start seeds indoors, when to direct-sow, and when to expect a bloom.

Save to Pinterest