Customer Service Hours
Mon-Fri 8-4 MST
Features
Family
Apocynaceae
Native
Brazil and Uruguay
Life Cycle
Annual
Plant Height
Tall (Greater than 24")
Flower Color
Blue
Bloom Season
Summer
Further Information
Plant Characteristics
- Attracts Pollinators
- Cut Flower
Plant Resistance
Deer Resistant
About Tweedia Milkweed/Butterfly Flower Seeds
Oxypetalum coeruleum
Aquamarine flowers approximately ½"–1" wide which fade to purple as they age
Planting Milkweed
Plant Spacing
A group of 2 to 3 seeds every 12" – 24"
Hardiness Zones
10, 11
Light Required
Full Sun to Part Shade
Plant Height
Tall (Greater than 24")
Planting Depth
¼"
Planting Details
| Seed Depth | ¼" |
|---|---|
| Seed Spacing | A group of 2 to 3 seeds every 12" – 24" |
| Thinning | When seedlings have 3 sets of leaves, thin to one every 12" – 24" |
| Germination | 21 – 28 Days |
| Start Indoors | 6 to 8 weeks before your average last frost date. |
| Direct Sow | 2 to 4 weeks before your average last frost date. Mild Climates: Fall for spring germination. |
| Special Sowing | Light aids germination; press seed into soil surface. |
Find Your Frost Date & Grow Zone
Average First Frost Date
October 19
Average Last Frost Date
May 19
Your Hardiness Zone is
5b
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Rating
Which best describes you as a gardener?
11 reviews
- RoseVerified ReviewerRated 3 out of 5 stars8/28/26Tweedia Milkweed
Spring of 2026 I tried 5 of these seeds to see if I could get them to germinate. I soaked the seeds for a couple of days but didn’t notice any swelling, so I planted them in some seed starter soil. It took more than two weeks, but all five seeds germinated and grew. I lost one seedling to a mishap, but the other four made it through the summer. None of the plants are very big, i.e. 4 inches tall max, and none of them bloomed. They are tiny, and since I’m Zone 8 I wouldn’t expect them to make it through the winter. I may try bringing them inside to see if I can get them through the cold weather, with the hope they may grow and bloom next season. They’re so slow growing I don’t think I would try them again unless I lived somewhere they might be perennial.
Which best describes you as a gardener? IntermediateBIBotanical Interests9/3/26Hey Rose,
Thank you so much for taking the time to share your detailed experience with our Tweedia Milkweed/Butterfly Flower Seeds. I really appreciate you documenting your growing journey with us, from the germination process all the way through the summer months.
It sounds like you had great success getting all five seeds to sprout and grow, even with the slow growth rate you observed. I'm sorry to hear that none of them bloomed this season and that you're concerned about their survival in your Zone 8 winters. Your thoughtful approach of potentially bringing them indoors to help them through the cold weather shows real dedication to giving them the best chance possible.
Your feedback about the growth timeline and performance is really valuable to us, and we appreciate you sharing how this variety worked out in your specific growing conditions. Thank you again for your input. Keep on growing 🌻
- Louis E.Verified BuyerRated 5 out of 5 stars8/26/26Milkweed seeds
These really did great for me and the butterflies this year, so I will be planting again and a few more this time around, than last year
Which best describes you as a gardener? IntermediateBIBotanical Interests8/29/26Hey Louis,
We're so stoked to hear that your Tweedia Milkweed/Butterfly Flower Seeds have been such a fantastic success! It's awesome that they did great for you and brought in the butterflies this year. We love that you're planning to plant even more next year - that's the kind of feedback that makes us so happy! Thanks so much for being part of the growing community! Keep on growing 🌻
- Kathy C.VA, United StatesVerified ReviewerRated 5 out of 5 stars1/16/26Beautiful milkweed
However, I live in Virginia and I've never had butterflies hover over it or lay their eggs on it. But I keep it because the color is beautiful and eye-catching.
Which best describes you as a gardener? IntermediateWho do you grow for? YourselfHow do you prefer to grow? In Ground - Staci B.Verified BuyerRated 5 out of 5 stars11/20/25Difficult to find these seeds
I love these flowers, so beautiful and delicate have bought them as plants in the past. Was happy to find seeds for them.
Which best describes you as a gardener? IntermediateBIBotanical Interests11/24/25Hey Staci,
Thank you so much for taking the time to share your experience with our Tweedia Milkweed/Butterfly Flower Seeds! We totally get how exciting it is to find seeds for those hard-to-find varieties - especially when you've fallen in love with them as plants before. We're so glad we could help you add these beauties to your seed collection so you can grow them yourself. Thanks for sharing your excitement with us. Keep on growing 🌻️
- Leslie O.Verified BuyerRated 4 out of 5 stars9/1/25Tweedia seeds look like Common Milkweed
I ordered a packet of Tweedia seeds and planted them this spring. They've grown lots of foliage so far this year, but no flowers yet. A Monarch Butterfly visited them this morning. And the leaves look like Common Milkweed plants? I'm going to try to transplant them to my new flower garden for next season and see how they do. Hoping to see more Monarchs!
Which best describes you as a gardener? BeginnerBIBotanical Interests9/9/25Hey Leslie,
Thank you so much for taking the time to share your experience. The leaves in the photo do have the wrong shape of leaves for Tweedia milkweed - but those leaves also don't look like other milkweeds; they look a bit like goldenrod (Solidago spp.) There's also a slight chance that it's ironweed (Vernonia fasciculata) - that's a native plant to the central US that has started spreading eastward but isn't found in the west.
If it's goldenrod, it's likely wild in your area and it should bloom soon with yellow flowers - while they usually start blooming in late August, it's still just barely into early September so there's still a chance. Thanks for being patient with them and for creating habitat for our precious pollinators.I've reached out to you via email to offer assistance. Your feedback is invaluable to us, and we are committed to ensuring your experience is positive. Thank you once again for your input. Keep on growing 🌻️