Winter Sowing Milkweed Seeds

Recently, I saw a post on Facebook about how to winter sow milkweed seeds using milk jugs.

Native milkweed seeds and many other perennial plants need a period of cold stratification in order to germinate. Cold stratification is simply exposing the seed to a period of cold treatment. I’ve always prepared milkweed seeds by using the artificial stratification method (click here for instructions), however, was intrigued by this unique method.

The holidays were spent at my son’s house in Michigan. I brought some milkweed seeds as a Christmas gift. He and his wife recently purchased a home and expressed an interest in planting a butterfly garden. I had planned to sow them directly into the ground but wanted to try using the “milk jug method” instead.

Using individual biodegradable planter cups to plant the milkweed seeds, I figured would make it easier to transplant the seedlings when they are ready. I placed potting soil inside the cups and watered the soil to moisten it, then three to four seeds were placed on top of the dirt and gently patted them down. (You do not cover the seeds with soil because they need light to germinate.)

Biodegradable 3″ Square Natural Fiber Pots

To prepare the milk jugs punch four drainage holes on the bottom of the jug using an awl. (You could also use the tip of a heated glue gun or drill the holes with a small power drill.) The holes need to be about ¼ inch in diameter to allow good drainage.  Cut the milk jug in half with sharp scissors, leaving about an inch for a hinge.

Leaving a hinge is essential to keep the top attached to the base.

Place the planter cups inside the milk jugs and use duct tape to seal them closed. Be sure to leave the caps off of the containers so the milkweed seeds will get watered from Mother Nature. I placed the milk jugs inside some planter trays for stability. Oh yes, and don’t forget to label the milk jugs! (I used a permanent marker, but a grease pencil will also work. Or you can use a planter label for each individual cup.)

Labeling your plantings eliminates confusion later in the season.

Now you just leave the milk jugs outside and let Mother Nature do her magic!

Even in the snow, the seedlings are protected inside the milk jugs.
You can purchase these native milkweed seeds here:

Click here for more detailed instructions on how to winter sow seeds using milk jugs:

Spread the message with this “Plant Milkweed” T-shirt by Butterfly Lady: