Monarchs and milkweed

Asked August 26, 2018, 9:31 AM EDT

Greetings. We have a field mowed every year. There is a an abundance of milkweed this year and we have been seeing monarchs so don’t want to disrupt that. I did some research and it seems that in September and October the last group of monarchs is hatching and this is the group that migrates. But we also want to keep our field from becoming woody. Soooo, when do you suggest we have it mowed? Thanks

Washington County Vermont

1 Response

Dear Monarch protector,

I suspect the best time would be when all signs of the butterflies have disappeared, which most likely would be in late October. Keep in mind that some of the butterflies you are seeing are focusing on preparing for the flight back to their overwintering sites and are more intent on stocking up on nectar from lots of different flowering plants. It is possible that even in Washington Co. the larvae have finished feeding and have emerged as adults. The adults don't feed on the leaves of the milkweed, only the nectar of the flowers. I suggest you contact an expert on this subject. The best way to start would be to go to the website

They have a section called Conservation Specialists

I would start by contacting one of the people listed for the Northeast region. If you don't get an answer that you find helpful, feel free to contact me directly at 802-656-5440. Email:

Margaret Skinner, Extension Entomologist