Ask Mr. Smarty Plants

The Monarch Waystation is a program of the The University of Kansas' Biological Survey Monarch Watch, not a program of the Wildflower Center, but we can certainly help with the milkweeds.

There are actually more than three species of Asclepias that grow in your area either in or adjacent to Hays County according to the USDA Plants Database and are available for sale as plants or seeds.  Here are the ones I have found listed by suppliers as being for sale as either seeds or plants:

1. Asclepias asperula (Spider milkweed) is avaliable from Native American Seed in Junction and is on the Wildflower Center's Plant Sale List.  Check the calendar for the next Wildflower Center Plant Sale.  Scroll down the species page for PROPAGATION information.
2. Asclepias tuberosa (Butterflyweed) is available at the Wildflower Center Plant Sale, at Natives of Texas in Kerrville, and from Native American Seed in Junction.  Here is the propagation protocol from the Native Plant Network.   
3. Asclepias viridis (Green antelopehorn) is available from Native American Seed in Junction and they will have propagation information with the seeds. 
4. Asclepias texana (Texas milkweed) is listed as available from Natives of Texas in Kerrville. You can find propagation information from Dave's Garden.

Although Asclepias incarnata (Swamp milkweed) is not shown by the USDA Plants Database as occurring in or adjacent to Hays County, it does occur as near as Burnet County.  It does, however, require moist or wet soil—thus its name "swamp milkweed"—but it is attractive and the butterflies love it.  It is shown as available on the Wildflower Center Plant Sale list and from Natives of Texas in Kerrville. Here is the propagation protocol from the Native Plant Network.

There are even more species of milkweeds that are native to your area of Texas but that aren't readily available commercially as plants or seeds.   Here are photos of Texas milkweeds.

You may check for other suppliers of native plants near you by searching our National Suppliers Directory.  I searched the database for suppliers of the milkweeds available for sale and looked on several of their webpages, but I did not check with all suppliers.  You can find seed germination instructions for several of the milkweeds on Tom Clothier's Seed Germination Database.  Additionally, the Monarch Watch webpage has an excellent article, "Growing Milkweeds", that should be very helpful.  You can also read an article, "Growing and Propagating Milkweeds", from the Butterly Society of Virginia.