New research from Michigan State University suggests that cutting back the milkweed patch can make it more appealing to Monarch butterflies as a nesting site. “Monarch butterflies scout young milkweed to lay their eggs,” said Nate Haan, MSU postdoctoral research associate in entomology and the study’s lead author. “And in terms of a food source, milkweed is more like spinach when it’s young and comparable to cardboard as it ages.”
According to “Mowing for Monarchs” in MSU Today “Anyone with milkweed in their backyard can experiment with mowing for monarchs to enhance egg laying success. Try mowing or trimming about a third of a milkweed patch in mid-June, when stems are starting to flower, and cut another third in mid-July when the mowed stems have regrown and are beginning to flower. Always leave the rest of the patch undisturbed.”
Here’s the full article: https://msutoday.msu.edu/news/2019/mowing-for-monarchs/