By Cathy Caldwell
Piedmont Master Gardener
It’s that time of year when lawnmowers come out of hibernation. But in a growing number of communities, the mowers are still doing nothing. Why? Because of a No Mow movement taking hold around the U.S. It’s not about laziness; it’s about providing forage for pollinators, particularly during the early part of the growing season.
In this country, the practice of No Mow May first took root in a Wisconsin college town. In our warmer climate, the Piedmont Master Gardeners encourage the community to adopt No Mow April as well as other measures to support beneficial insects.
This movement seems at odds with Americans’ love of their lawns. Large expanses of lawn became popular in France and England in the 18th century among the upper classes. By the end of the 19th century, the use of lawns had spread to the U.S. largely through the influence of Frederick Law Olmsted, co-designer of New York’s Central Park. With the rise of suburban communities around the country in the next century, a front yard with a well-manicured grass lawn became the standard and a symbol of success.
According to a 2005 NASA study, there are more than 40 million acres of residential and commercial lawns, golf courses and parkland in the U.S. These turfgrasses represent 2 percent of the land in the continental U.S. and are the single largest irrigated crop in the country. Lawns are a heavy consumer of resources (water, fertilizers and pesticides), a source of pollution of our watersheds, high maintenance and expensive.
While turfgrass provides little natural habitat or food for bees, butterflies and other pollinators, most lawns nevertheless harbor flowering weeds that native bees and other pollinators need. Even weeds like dandelions provide essential pollinator food—nectar and pollen—early in the season when flowering plants are in short supply. In fact, dandelions are a superfood for bees and butterflies. According to one study, dandelions produced 9 percent of the lawn’s pollen and 37 percent of its nectar sugar.
Because human activities like development and intensive farming have contributed to a decline in the number of pollinators and reduced the supply of pollinator nutrition, we must do all we can to remedy that shortfall. As vegetable gardeners know, food production depends in large part on pollinators. According to the U.S. Forest Service, almost 80 percent of the 1,400 crop plants grown around the world require pollination.
Leaving weeds to flower by not mowing for a month is the simple idea behind this growing movement. No Mow May started in the United Kingdom in 2019 and jumped the pond in 2020 to Appleton, Wisconsin, at the urging of professors Israel Del Toro and Relena Ribbons.
In that first year, 435 Appleton residents signed up to participate in No Mow May. Del Toro and Ribbons then gathered data on the impact. They discovered that the No Mow lawns had five times the number of bees and three times the bee species as nearby mown areas in town parks. In 2022, at least 25 U.S. cities participated in the No Mow initiative, adopting April or May depending on the start of the mowing season, when temperatures consistently reach at least 40°F.
Del Toro considers it only a starting point for bee conservation. “What you did for one month, that’s cool, that helps,” he said. “But what are you going to do the rest of the summer, or the rest of the year, to make sure that our pollinators are protected?”
For those next steps, Penn State’s Pollinator Research Center advocates strategies such as the “lazy lawn mower” approach. Mow less frequently or at a higher mower height to sustain low-flowering plants in your lawn that provide pollen and nectar resources for foraging bees, such as dandelions, bird’s-foot trefoil and clover. University of Minnesota Extension promotes “the one-third rule”: Mow no more than one-third of the lawn at one time to a height of 3.5 to 4 inches, allowing flowering plants to survive and produce flowers.
Since a tidy, well-mown lawn may be required by local ordinances or HOA rules, most No Mowers have found it helpful to post a sign alerting neighbors to the purpose of their “lazy lawn mower” practices. Most communities implementing the No Mow initiative have enacted ordinances authorizing participants to leave lawns un-mown for the month.
Here are some more options to consider:
Establish a “bee lawn” by cultivating flowering plants in your turfgrass. According to experts at Minnesota Extension, Dutch white clover (Trifolium repens), self-heal (Prunella vulgaris) and creeping thyme (Thymus praecox ssp. arcticus; formerly Thymus serpyllum) benefit pollinators and will flower in a mowed lawn. Plus, white clover tolerates drought and adds nitrogen to the soil.
• Create a pollinator habitat in your yard by planting native plants with a variety of blooming times, so that nectar and pollen are available throughout the season, along with nesting places and water resources.
• Mow less throughout the growing season. Instead of mowing once a week, mow every other week.
• Limit the lawn area by leaving areas uncut, enlarging garden beds, planting groundcovers or establishing “islands” of edible or ornamental plants in the middle of the lawn.
• Use lawn best management practice, following this checklist from Virginia Cooperative Extension: pwcva.gov/assets/documents/vce/006791.pdf.
• Reduce or avoid herbicide, insecticide and pesticide use in the lawn. If using chemicals, follow the recommendations of Virginia Cooperative Extension’s 2023 Pest Management Guide. To find it, search online for VCE publication 456-018.
• Educate yourself and others about factors related to pollinator decline. Pollinators are critical to our food security, so we all need to know why they are threatened and how to protect them.
Local residents may also want to take advantage of the Piedmont Master Gardeners’ Healthy Virginia Lawns program, which provides an on-site visit, soil analysis and assessment of your lawn, or PMG’s new Healthy Landscapes program, which provides a site assessment and recommendations for establishing habitat in your yard that supports our native flora and fauna. Visit piedmontmastergardeners.org/conservation-landscaping/ for details.