Rhoda and Leonard Bernstein have a "No Mow May" sign in a prominent place in their yard. They're one of more than 300 Edina residents unapologetically letting their grass grow in the coming weeks.

The effort is part of an international movement to encourage homeowners to postpone cutting their grass in spring. Proponents say that leaving grass unshorn helps pollinators such as bees thrive during the crucial post-winter period, when they are coming out of hibernation.

Suspending mowing allows flowering plants that grow in the grass — such as clovers and dandelions — to bloom, which provides pollinators and their offspring with nectar and pollen. In addition, taller grass can give shelter to bees and butterflies.

"You work with Mother Nature instead of against her," Rhoda said.

The movement, founded in 2019 by an environmental group in the United Kingdom, has spread across the globe and is gaining steam locally.

Some Twin Cities residents have taken part in No Mow May on their own. Others are beginning to work with local governments to temporarily halt turf ordinances. That way, residents can join No Mow May without violating nuisance laws.

In addition to Edina, Monticello, Vadnais Heights and New Brighton are among the Minnesota cities participating in No Mow May for the first time. Those municipalities will not enforce city codes that restrict lawns from exceeding a maximum turf length (10 inches in Edina and Vadnais Heights, 8 inches in Monticello and New Brighton) during the month of May.

In some cities, participants must register. In Edina, 310 households have signed on. Residents have the option of picking up "No Mow May" signs at City Hall to place in their yards.

"That allows our weed inspector, who enforces those ordinances, to know they're participating if they receive a complaint," said Grace Hancock, Edina's sustainability manager. In addition, "it promotes the program and it makes the program visible. Some people might not know about it and this lets them know why their neighbors' yard is going unmowed."

And even if residents decide not to participate, No Mow signs create conversation about the importance of providing pollinator-friendly spaces.

In Vadnais Heights, the city council passed a No Mow May resolution on Tuesday. Resident Judy Lissick, who has volunteered on local climate action committees, was the driving force behind the resolution, which she views as a starting point in promoting biodiversity — during the month of May and beyond.

"It's not a one size fits all, and we're not telling people what to do with their lawns," Lissick said. "For people who can't stand the dandelions and weeds, they can cut their grass really short [to 1 inch] for the first time in May to allow your grass to get a good start with a healthy root system."

"It's not going to do anything for pollinators, but it will provide healthier soil for [all sorts of] wildlife," she said. "Then after that, you never cut your lawn shorter than 3 inches to maintain a healthy root system."

Success stories

Rochester may have been on the no-mow cutting edge in 2020, when it amended its public nuisance code to allow grass to grow taller than 12 inches in May. In 2021, North Oaks and West St. Paul followed suit. All three cities plan to participate in the program again this year. In West St. Paul, that means residents have the option to grow grass past the permitted 8 inches in that month.

A council vote is slated for Monday. If passed, the city of West St. Paul plans to provide "No Mow May" signs to residents.

Participating cities are bracing for complaints.

Last year, West St. Paul received about 20 lawn-related complaints in May, though it was difficult to determine how many of those were related to No Mow May. Officials hope that a citywide information campaign will cut the number of complaints and help track homeowners who are taking part in the program.

"Last year was really a trial run of sorts and we didn't require any sort of registration, so [there was] no way for us to quantify," said Dan Nowicki, assistant city manager. Those who did call in to report a complaint "were not upset and were very understanding once we explained the situation."

There is evidence that No Mow May efforts already are paying off.

In Wisconsin, several cities including Stevens Point, Wausau and Oshkosh have participated in No Mow May. A 2020 study by Lawrence University showed three times the variety of bee species and five times the bee count in the yards of registered no-mow participants compared to nearby parks that were mowed, according to Bee City USA, a Portland-based nonprofit.

You don't have to convince homeowners like the Bernsteins that No Mow May is the bees' knees. Well before it was allowed by Edina, they were No Mow May enthusiasts. Even getting citations from the city for the length of their grass didn't deter them.

"We're seeing dragonflies, butterflies and certainly more bees and more varieties of bees," Rhoda said. "And because pollinators are more prolific, we get more flowers. And when we get more flowers, we get hummingbirds.

"The best part about it is it doesn't cost anything to do it and it makes such a big difference."