How to Get Texas Native Milkweed Seeds to Germinate

Our friends at Native American Seed have been working for years on the best way to get persnickety Texas native milkweed seeds to germinate.   “Native milkweeds simply don’t do well in containers,” said George Cates, seed wrangler at the seed farm and land restoration company in the Hill Country town of Junction.  “They require a very specific set of conditions and have an extremely long tap-root, making containerization untenable.”

Want native Texas milkweed?  Start with seeds.  Photo courtesy Native American Seed Co.

Want native Texas milkweed? Start with seeds.

So what’s the solution to getting native milkweeds into our landscape?  Start with seeds.

The process has been perfected by Cates, who has germinated thousands of seeds in the last year for Native American Seed‘s customers and the Xerces Society.    Read a report about the project and the status of native Texas milkweed seed production here.   Here’s Cate’s process:

Milkweed Stratification Procedures, Courtesy Native American Seed

NOTE:  Cates insists that sterile rubber (latex) gloves be worn at all times and that containers and implements be sterile.   Otherwise, mold can grow in the vermiculite and damage the seeds.

1. Mix seeds with pre-chilled distilled water and let soak for 24 hours in the fridge.

2.  After 24 hours, pour seeds into strainer and rinse with distilled water.

3. Moisten vermiculite with distilled water, the exact quantity required varies with different media, moist but not dripping is best.

4.  Mix rinsed seeds into vermiculite using your hands, and wear sterile gloves.

5.  Seal container and store in fridge for 30-45 days at 35-45 degrees.  Remove and plant immediately if you see mold.

6.  Plant entire mixture or sift seeds out and plant in prepared seed bed when soil temps are warm (70 degrees+).

7.  Water often until germination occurs.


Antelope horns milkweed, a Monarch butterfly host plant, in bloom.  Photos by Native American Seed

Antelope horns milkweed, a Monarch butterfly host plant. Photos by Native American Seed

Soaking and washing the seeds removes natural chemicals that inhibit germination.  When the seeds are moved from the cold darkness of the refrigerator to the bright light and warmth of the sun, they are “shocked” into sprouting.  “The stratification process is meant to mimic nature,” he said, adding that the plants likely developed this dormancy strategy as an answer to drought conditions.

Good luck with your milkweed seeds and let us know how it goes!

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11 thoughts on “How to Get Texas Native Milkweed Seeds to Germinate

  1. Thanks for what you are doing. I hope to try this if I can get the seeds. I’d like to try to find some of the native seeds for this.

  2. I have just received 64 little 3-4″ tall Milkweeds to plant throughout my yard and big new flowerbed…I got anxious and did not do this in the Spring..I heard we are to have a hard winter … would you greenhouse these babies or go on and set them out…I just got so excited I ordered. They did not tell me the variety but said they would send per my area…thank you.

  3. Mr. Cates, thank you for your efforts to help the monarchs and for promoting native plants. I plant Pennsylvania native milkweeds using seed balls and fall plant them with good success. I think the our Common milkweed in germinates a little easier than your species, though. Germination rates among Asclepias seems quite variable. It is great that you developed such a sure fire method for yours, and that you shared it online!

  4. What’s the expiration on old seeds? I have some that are a couple of years old to 5+ years old that are in my seed stash. Would love to try them but if they won’t work, I need to throw them out.

  5. How long are the taproots? I just read that they are long, but never how long. I would guess the length varies a bit between the types.

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