I have a similar project in process on my 147 acres in southeast Indiana. I bought 1/2 lb. of Asclepias syriaca from www.prairiemoon.com
. That's about 32,000 seeds to be mixed with a portion of the warm season grasses and other wildflowers for about 2 acres. Another 13 acres will be planted (all via a seed drill) with the warm season grasses and wildflowers, including Asclepias tuberosa. There's some wild A. syriaca and A. tuberosa already growing for this year. (I was thrilled to see a monarch laying eggs 2 days ago!) What we're planting this year will have to winter over before it will germinate. An additional 10 acres will be cleared of honeysuckle and honey locust to make it practical to plant next year. Good luck with your project, Kamic!