No Mow May is a conservation campaign that encourages people to stop mowing their lawns for the entire month of May, giving wildflowers a chance to bloom and providing food for bees, butterflies, and other pollinators during a critical time of year. The idea started with the UK conservation charity Plantlife and has since spread across North America and Europe. The science behind it is compelling: unmowed lawns produce fivefold higher bee abundance and threefold higher bee species richness compared with regularly mowed areas.
What No Mow May Actually Does
When you stop mowing, flowers that would normally get clipped before they open, like clover, dandelions, and creeping buttercup, get a chance to bloom. These low-growing wildflowers are some of the earliest and most important food sources for pollinators emerging in spring. A study in Appleton, Wisconsin found that unmowed lawns had 36% more plant species and 34% higher flower density than regularly mowed green spaces.
That burst of flowers translates directly into more pollinators. The same study recorded nearly five times more bees and three times more bee species on unmowed lawns. Separate research from suburban Massachusetts found that lawns mowed every three weeks produced up to 2.5 times more flowers than lawns mowed weekly. Interestingly, that study also found that lawns mowed every two weeks supported the highest number of individual bees, though with less species diversity, suggesting there’s a sweet spot between total neglect and frequent cutting.
The Case for Going Beyond May
Plantlife now frames No Mow May as a starting point rather than a one-month event. Their updated guidance encourages people to let lawns bloom through May and into summer, with a broader “No Mow Movement” that extends through June and beyond. The core recommendation is to maintain two to three different grass lengths across your yard throughout the growing season:
- Long areas: Left unmowed all year, allowing taller wildflowers like oxeye daisy to complete their full bloom cycle.
- Mid-length patches: Mowed just two to three times a year, kept long from April or May through August to support summer-flowering plants.
- Short sections: Mowed once a month to a height of one to two inches, giving you usable lawn space while still reducing overall cutting frequency.
This mosaic approach balances pollinator habitat with a yard that still looks intentional. Lawns left long from spring until mid-July and then mowed regularly will return to a typical green carpet look for the rest of the year. If you leave the grass until September, though, the appearance may change more permanently for that season.
Potential Downsides to Consider
Letting your grass grow tall for a month isn’t without trade-offs. Ticks thrive in tall, moist grass. They climb to the top of grass blades and wait with their front legs outstretched to latch onto passing people or pets. Harvard’s Lyme Wellness Initiative specifically recommends keeping grass mowed short as a tick-prevention strategy, particularly in regions where Lyme disease is common. If you live in a tick-prone area, you may want to keep the unmowed patches away from walkways, play areas, and spots where pets spend time.
There’s also the question of regional timing. May works well in the UK, where the campaign originated, because it aligns with the peak spring bloom. But in the southern United States, wildflowers may peak in March or April, while in northern climates the meaningful bloom might not arrive until late May or June. The pollinator benefits depend on flowers actually being present, so adjusting the timing to match your local growing season makes more sense than rigidly following the calendar.
HOA rules and local ordinances can also be a practical barrier. Some municipalities have grass height limits, and neighbors may not share your enthusiasm for a wilder-looking yard. Checking local regulations before committing saves headaches.
How to Start Mowing Again Without Damaging Your Lawn
The biggest mistake people make after No Mow May is firing up the mower on June 1st and cutting everything down to two inches. Removing more than one-third of the grass blade at once shocks the plant, dehydrating it and leaving brown patches. This is sometimes called “scalping,” and it can thin out your turf enough that weeds move in.
Instead, ease back into mowing gradually. Set your mower to its highest setting for the first cut, removing no more than a third of the blade height. Then wait two to four days and cut again, lowering the deck slightly each time. Depending on how tall the grass got, this step-down process takes anywhere from several days to about two weeks. It feels tedious, but your lawn recovers much better than it would from a single aggressive cut.
If the grass grew especially tall and thick, you may need to use a string trimmer first to knock it down before the mower can handle it. Collecting the clippings during these initial cuts helps too, since heavy mats of cut grass left on the surface can smother the turf underneath.
A Low-Mow Approach Year-Round
You don’t have to choose between a perfectly manicured lawn and total rewilding. The research consistently shows that simply reducing mowing frequency provides real benefits for pollinators. Mowing every two to three weeks instead of weekly produces significantly more flowers and supports more bees. This is a change most people can maintain all season without their yard looking abandoned.
Raising your mowing height by even half an inch helps as well. Taller grass shades the soil, retains moisture better, and allows low-growing flowers like clover to bloom between cuts. If you stop treating clover and dandelions as weeds and let them flower before you mow, you’re providing pollinator food with almost no effort. The simplest version of No Mow May isn’t really about May at all. It’s about mowing less often, cutting a little higher, and tolerating a few more flowers in your grass.