Asclepias tuberosa is easily propagated from seed. Collect seeds after the pods have ripened, but before they have split open. The seeds are wind dispersed, so be careful when gathering to place in a paper or burlap bag to avoid losing them. Butterfly milkweed seeds should be cold-treated for three months. Seeds can be directly sewn into the ground in the fall. The seed is very viable. It is not certain how long you can store the seeds.
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