Parcel
No. 4$4.50 Butterfly Milkweed
Illustration of the No. 4 Butterfly Milkweed seed packet: a kraft envelope with the Missouri Native Series stamp label and a SOW DEC–FEB postmark on the front, and the growing directions and label details on the back.
The packet

No. 4 in the Missouri Native Series

Butterfly Milkweed

Asclepias tuberosa

Missouri Native Series No. 4. Bright orange monarch host plant for hot, dry, sunny ground. Blooms June–August, 1½–2 ft tall.

$4.50packet

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Free shipping on orders of $25 or more, or on any order with a Winter-Sow Kit, The Complete Series or a Seed Club membership. Otherwise $3.95. Ships in 2–4 business days. We ship to the 48 contiguous states and D.C., except Colorado, Kentucky, Minnesota, Nebraska, Ohio, Pennsylvania and Wisconsin for now. Shipping details

  • Missouri native seed, packed for 2027
  • Postmarked to sow December to February, outdoors (winter sowing)
  • Grow Guarantee: if it doesn't come up after you follow the guide, we'll send a replacement

Bright orange and built for hot, dry ground, butterfly milkweed is one of the monarch’s host plants and a magnet for butterflies of all kinds. It grows statewide in Missouri’s prairies, glades and open woods. The Missouri Department of Conservation says coral hairstreak butterflies are “addicted” to the blossoms.

Unlike most milkweeds, its sap isn’t milky, and it isn’t weedy. It’s patient, though: the deep taproot takes a year or more to build, and it’s one of the last plants up each spring, so mark where you sowed it.

It needs a winter chill to sprout. Each packet is hand-filled in St. Charles County, Missouri.

Good to know

  • Toxic if eaten. Keep pets and livestock from grazing it.
  • Sap can irritate skin and eyes; wear gloves if you’re sensitive.
  • Late to come up in spring. Mark the spot so you don’t dig it by mistake.
  • Aphids are common on milkweed. Leave them for ladybugs, or rinse them off with a strong spray of water or soapy water.

How to grow

  1. Pick its forever spot. Full sun and well-drained soil. It grows a long taproot, so sow it where you want it to stay, or in a deep container and move it while it’s small.
  2. Sow in late fall or winter. Between November and February, sow on bare, weed-free soil or in a deep winter-sowing jug, about 1/8 to 1/4 inch deep. See our winter sowing guide.
  3. Or use the fridge. Chill the seed in damp sand for 30 days, then sow after the last frost. Here’s the fridge method.
  4. Mark the spot. Established plants come up late in spring. Don’t dig there by mistake.
  5. Give it time. Prairie Moon says it can take one to three years to bloom from seed. Expect leaves the first year.
  6. Let the caterpillars eat. Chewed leaves mean monarchs found it. Aphids are common on milkweed; leave them for ladybugs or rinse them off with water.

Good neighbors

Species from the series that grow well alongside Butterfly Milkweed:

Questions

Do monarchs use butterfly milkweed?

Yes. It’s one of their larval host plants. Prairie Moon notes monarchs often prefer other milkweeds for laying eggs, which is why our Monarch Milkweed Trio pairs it with Swamp and Common Milkweed.

Is butterfly milkweed safe around pets?

No plant in this genus should be eaten. The ASPCA lists milkweeds as toxic to dogs, cats and horses, and NC State Extension notes the sap can irritate skin and eyes. Plant it where pets and livestock won’t graze it.

Why hasn't my plant come up this spring?

Give it time. Grow Native! notes it has a deep taproot and is slow to emerge in spring. It’s often one of the last plants up.

Will it spread like common milkweed?

No. The Missouri Department of Conservation describes butterfly milkweed as not weedy. It grows from a deep taproot.

Sources for these facts