No Mow May — maybe a no?

Lawns are greening up and growing like crazy. You may be tempted to employ the technique titled "No Mow May." But what is wrong with letting your lawn grow for the whole month of May without cutting it? If you are concerned about the health of your lawn, there are potentially some downsides to this practice. No Mow May originated in the United Kingdom to support pollinators. Many of the weeds in our lawns like clover and dandelion are a source of pollen for bees and other insects. The idea was that if we let our lawns grow without mowing, the weeds will provide pollen. Of course, by definition a weed is a plant growing where it is not wanted and so in that regard, beauty is in the eye of the beholder. City ordinances may also have an impact on this statement, too. Findlay is one of those cities that requires owners to keep their grass below a certain height. Further, the only piece of research that was published regarding the No Mow May initiative was retracted due to data issues and thus we are in a quandary as to the efficacy of the approach as compared to flowering trees in the landscape. With regards to dandelions in particular, Dr. David Gardner, Horticulture Professor at The Ohio State University, states, "In Ohio, dandelion peak bloom is April, clover peak bloom is late May into June. Peak grass growth is May. To me it almost makes more sense to tell folks not to mow in April or June or both and properly mow to ensure turf density in May. The weeds that peak in May for bloom are some of the winter annuals, like Veronica, but also ivy and violet and these are not the weeds we necessarily want to give an advantage." But not mowing for the whole month of May will mean your lawn may be approaching a height of 12-24 inches depending on species and climatic conditions. If the lawn is mowed down to a recommended height of three inches the first of June, the lawn may go into shock, the crown will be exposed and as we get into the drier months of summer, the grass plants may suffer and even die. Reseeding might be necessary in September to bring back the turf which will cost time, money and effort. Dr. Edward Nangle, Turf Specialist for The Ohio State University, says, "While there is an understanding of the potential for this idea, there is concern that a lawn cannot be returned to previous conditions and thus will homeowners accept the new norm – we do not know. Further to this if voids are created opportunities for soil erosion and weed encroachment will occur — again will homeowners accept this and is there a potential concern regarding water pollution with soil erosion potentially increasing?" As people who live in the country have learned, mowing restricts the presence of unwanted visitors such as ticks and chiggers. Chiggers are uncommon in Northwest Ohio, but warmer conditions will move them north. Tall weeds and grass are excellent habitat for rodents and small mammals which will bring the ticks and chiggers to your yard. Currently, Ohio State University researchers are comparing traditionally maintained yard type surfaces and a lower input situation to observe their long-term effect on lawn condition. Updates will be provided via Turf Team Times and other outlets that the OSU Turfgrass Team uses including social media. This topic was briefly discussed at minute time stamp 11:00-15:30 in a recent Turfgrass Team Times recording that is produced by the turf team at OSU. The link of the recording may be is found at https://www.youtube.com/watch?v=A9YeFTquI-U. Researchers continue to investigate the No Mow May concept. So, what about the pollinators? The pollinators are smart enough to find a smorgasbord of flowering plants during the month of May. Look outside. There is a ton of pollen available. Ask anyone allergic to pollen. With regards to a healthy lawn, a recommendation is to mow at a blade height of around three inches and not to remove more than a third of the blade. This means you may be mowing every four or five days in May. But do not worry, the grass will slow its growth throughout the summer months. Our Cool Season grasses go into a state of no or slow growth in the hottest part of the summer. You may go two weeks without mowing. I know you are thinking if you cut your lawn short, say two inches, it really looks kept. The temptation is to make our turf look like a golf green. For most homeowners, this is not practical or cost-effective. So, what is a homeowner to do? University turf specialists recommend: · Mow at a height of around 3 to 3 1/2 inches · Do not remove more than a third of the blade. · Perennial weed control is most effectively done in the fall. · Reseeding is most effective in early September when soil temperatures and moisture are high. · Do not remove grass clipping. Mulching them returns nitrogen to the turf. · Fertilize sparingly and sweep or blow off any fertilizer on walks and driveways back into the turf. So, although No Mow May sounds like a good idea, there is still plenty of pollen from other sources besides weeds growing in the yard. This week's column was adapted from an Extension article written by Dr. Edward Nangle, Dr. David Gardner and Thomas deHass (https://bygl.osu.edu/index.php/node/2137). Lentz is agriculture and natural resources educator for Ohio State University Extension — Hancock County.