RE: Locating Poke Milkweed Seeds

(Question)

Hello! I have a balcony here in Toronto where I can grow plants. The climate zone is 6A to 7A. It is mostly shade but does get the late afternoon/ setting sun. I would like to grow Milkweed for the butterflies. The majority of Milkweed, however, seems to need full sun. As far as I can find out Poke Milkweed can grow in shade. My problem is that I can not locate an supplier for the Poke Milkweed; most firms only have Milkweed varieties which have to have sun. It would be great if you tell of any suppliers that have the Poke Milkweed seeds or plants. The soil is a mix of compost/ peat/ and leftover from purchased plants. I sow clover seeds each year to build up the dirt. The soil needs to be watered once a week or so, it stays fairly moist in the spring/ summer/ fall but dries out completely in the winter. I hope this is enough information. Many thanks, Best regards.

(Answer)

Thank-you for contacting Toronto Master Gardeners with your question about growing milkweed on your balcony. It is always great to be able to encourage gardeners to grow native plants for our pollinators! As you have discovered, Poke Milkweed (Asclepias exaltata) is the only native milkweed that actually prefers part-shade over full sun. It is a lovely tall plant with broader leaves than many milkweeds and sweetly scented dangling flowers. It benefits not only Monarchs but also other native pollinators. It is less commonly found in the wild in Ontario than some of the other milkweeds (this may be one reason why a source is difficult to find). As a matter of policy, Toronto Master Gardeners does not recommend any individual suppliers but you can get a list of your local nurseries at the  Landscape Ontario  website.

One other milkweed I looked into, Swamp Milkweed (A. incarnata) is considered to be somewhat shade-tolerant. If you are unable to find a source for Poke Milkweed, you may wish to give this more readily available alternative a try. It has attractive pink flowers and tops out at about 3 to 4 feet – a little shorter than Poke Milkweed. It does require a consistently moist environment.

The following links will take you to articles with additional general information on growing and maintaining Poke Milkweed (and other milkweeds):

Ontario Wildflowers

Native Milkweeds for Ontario Gardens

Monarch Butterfly Garden

Best of luck with your search!