I included some milkweed this year in a planter I maintain across from my house in Seaton Village, Toronto. It’s looking quite yellow and sad now (mid-October), and I’m wondering if the monarch butterflies still need it this late in the year. Would it already have reseeded itself, and would it be best to just pull it up? Thanks for any information!
Thank you for contacting Toronto Master Gardeners with your question.
In their caterpillar stage, the monarch’s sole source of food is the milkweed plant. Monarch butterflies lay their eggs on milkweed plants and the caterpillars emerge three to twelve days later. They feed on milkweed leaves for two weeks and mature into a chrysalis. Once they emerge as adults, they can start sipping nectar from a variety of native flowers. Some favourites are echinacea, black-eyed susan, sage, goldenrod, zinnias and dahlias. In autumn adult monarch butterflies are ready to migrate south to Mexico.
You can see that monarch butterflies don’t still need milkweeds for feeding themselves by the end of October. As milkweeds are perennials, you just have to cut them back to the ground and they will come back next year.
The following websites provide additional information on monarch butterflies life cycle:
Here are links to previous Toronto Master Gardener posts on milkweeds, which you may find informative: