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Finding and Collecting Milkweed

Finding Milkweed | Growing Milkweed | Catching Monarchs | Making a Cage | Rearing Monarchs

Seed Collection / Storage

Collect your seeds when the milkweed pods are ready to burst (this occurs in the fall in the northern United States). Once you have collected seeds, remove them from the pods and store them in an airtight container in a cool and dry environment (such as a basement or garage) until you are ready to use them. It is best to include a moisture remover (i.e. Silica gel) in your seed storage container. If the seeds are moist for a long period of time, they will start to rot and eventually die. Seeds collected in the Northern US will not germinate without cold stratification (see the growing milkweed section for further information); most tropical species can be planted without this pre-treatment.

If you want to purchase seeds, check out the following websites: and There are a variety of milkweed species to choose from, so you might want to experiment with a number of species to begin with.

Plant Collection / Storage

Most milkweed species grow particularly well in disturbed areas, so take a look in the following places:

  • monitoring locationRoadsides
  • Pastures
  • Along railroad tracks
  • Bike paths
  • Highway medians
  • Agricultural fields
  • Vacant land
  • Cultivated gardens
  • Parks

When collecting milkweed, it is best to pick the entire plant (check the plant for invertebrates to ensure you don't take any unexpected critters home with you). You can pick several days worth of milkweed and keep it in a plastic bag in a refrigerator. Wash it in water before using it. Milkweed stays fresher if you keep the end moist by wrapping it in a wet paper towel and then covering it with aluminum foil, or use florist water tubes or soda bottles.

Plants can also be purchased from your local nursery.

Female adult monarchs have a milkweed preference when laying their eggs. To find out what their favorite is, read this article from our 2005 MITC Newsletter.