No Mow May: A Well-Meaning Mistake for Ontario Bees
The hidden costs? Invasive plants, empty calories, and eco-placebo.
No Mow May has taken off as a feel-good environmental movement. After all, who wouldn’t love helping bees by doing nothing? The hopeful thing about this movement is that people are starting to recognize how ecologically barren traditional lawns are and are showing real commitment to supporting pollinators. But while the idea is popular, No Mow May in Ontario is a well-meaning distraction. Instead of helping our native bees, No Mow May can facilitate the spread of invasive plants and create confusion around which plants we need to support Ontario’s biodiversity.
One Month of “Lazy Lawns” Isn’t Enough
The first issue with No Mow May is that it’s just one month of letting lawns grow. Once June arrives and the mowers are back out, any temporary nectar and pollen sources disappear. Native bees and other pollinators need sustained floral resources throughout the growing season—not just a brief buffet in May before the food supply is abruptly cut off.
A study by Larson et al. points out that while some early-season bees might benefit, the winners are often generalist species like honeybees, which are not native to Ontario and are not endangered. In fact, honey bees can crowd out our native bee species! It is our native pollinators that are struggling and need critical support, and they need native plants in bloom from spring through fall. If we want to make a measurable difference, we need to think beyond a single month of letting whatever is in the seed bank grow.
Urban Lawns Are Full of Invasive Plants
Most suburban and urban lawns in Ontario aren’t hiding a secret meadow of native wildflowers. Sadly, colonization and unsustainable development replaced diverse native plant communities with turfgrass and exotic ornamentals, devastating biodiversity. Most urban and suburban seed banks are now dominated by the non-native plants settlers brought with them—many of them invasive.
When we let lawns grow wild, we’re often just encouraging invasive and non-native weeds like creeping Charlie, garlic mustard, and creeping bellflower to flourish—plants that crowd out the few remaining native species that our pollinators actually need.
Lawn dominated by creeping charlie.
Non-Native Weeds ≠ Good Bee Food
Even if a lawn isn’t overrun by invasive species, the most common "weeds" (like non-native dandelions) aren’t great for native bees. Many native bees have evolved alongside specific native plants and can’t thrive on non-native substitutes.
Ontario bee and native plant experts Dr. Sheila Colla and Lorraine Johnson explain that while dandelions provide some support, they’re like junk food for bees—low in nutritional quality compared to native flowers. Dr. Colla cites a study of North American queen bumble bees which found that they actually resorted to eating their own eggs when they fed solely on dandelion pollen. Early blooming Ontario native trees provide much better sustenance for our pollinators.
Dr. Colla writes: “There’s huge value in challenging monocultural lawns and the enormous ecological damage they have caused, but offering a feel-good moment of aesthetic rebellion risks obscuring, and even undermining, the bigger goal.”
If the goal is to feed, and save, the bees that need saving (ie. native bees), a lawn full of dandelions for one month of the year simply won’t cut it. We need intentional reductions in non-native exotics and (ideally) lawn cover, and an increase in native plant communities. No Mow May therefore risks becoming an eco placebo—making people feel green while delaying real change.
Eastern Redbud, an early flowering native Ontario tree.
No Mow May Was Designed for the UK—Not Ontario
No Mow May originated in the UK, where dandelions are native and actually support local pollinators. But in North America, the ecology is completely different, and there’s surprisingly little scientific backing for No Mow May’s effectiveness here. Instead of relying on a UK-born trend, we should focus on intentional habitat restoration—planting diverse native species that will sustain pollinators all season long.
Beyond No Mow May in Ontario
If we really want to help bees, we need to do more than skip mowing for a month. Here’s what actually works:
✔ Replace lawn sections with native gardens (even small patches help!).
✔ Plant a succession of blooms so pollinators have food from spring to fall.
✔ Leave leaf litter and bare ground for nesting bees.
✔ Avoid pesticides—even "weed-and-feed" lawn products harm pollinators.
As Bee City Canada suggests, No Mow May can be a starting point—but it shouldn’t be the end goal. No Mow May has raised awareness about sterile lawns, but in Ontario, it’s at best a conversation starter and at worst a boost for invasive species. If we want to save pollinators, we need to replace lawns with real habitat.
So, skip the trend. Plant natives instead.
