The Buzz on No Mow May

Photo from Pollinator Friendly Alliance

There has been a considerable amount of publicity about “No Mow May” and many individuals have committed to following this practice. What benefit will this offer to the environment or to beneficial insects?

If your turf is a showcase of beautifully manicured turfgrass, it will provide essentially no benefit to pollinators and can be mowed with no regrets during May, weather permitting. In fact, allowing lawn to grow long, then mowing more than the recommended one-third off is hard on both the turfgrass and the mower.

However, lawns that contain low growing plants like dandelion, clover, and creeping Charlie (some might call them weeds) can certainly provide benefit to pollinators. These lawns would be a great place to allow to grow during the month of May when the options of nectar and pollen are limited.

To make a lawn pollinator friendly, consider incorporating some of the low growing, pollinator friendly plants. Dutch White Clover (Trifolium repens), Self-heal (Prunella vulgaris) and Creeping Thyme (Thymus serpyllum) are all excellent choices.  These can used with conventional turfgrasses like Kentucky bluegrass and fine fescues without taking over. They can tolerate both mowing and foot traffic and have a perennial life cycle, so do not need to be replanted each year. University of Minnesota has an excellent bulletin that explains this in more detail entitled “Planting and Maintaining a Bee Lawn” https://extension.umn.edu/landscape-design/planting-and-maintaining-bee-lawn#when-to-establish-a-bee-lawn-2941610

To keep the lawn pollinator friendly, reduce or eliminate the use of pesticides.  Wisconsin lawns seldom have a need for pesticides.  If a need arises, confirm the pest and the need, consider spot treating, and, if possible, delay it beyond a spring application. Choose the least persistent, least toxic method and read the label carefully for proper application.

When May is over, it may take several passes to get the lawn back to the desirable height.  For best turf health, keep the lawn at 3-4 inches for the remainder of the season.

The lawn is not the only place that can be made pollinator friendly. Pollinators need food, water, and shelter like any other living organism. In the spring, the eggs and larva need an opportunity to develop before they get disturbed.  Therefore, do not clean up perennial beds until late May (or until the temperatures have risen to 50 degrees) to allow time for them to emerge as adults. Many native bee species use hollow stems as nesting sites, some butterflies and other insects are imbedded in the debris around hostas and other perennials. So, pause for a beat and give them opportunity to mature.

Plant a wide variety of trees, shrubs, and flowering plants to provide food.  Make sure something is blooming from April to October.  Allow for different heights and forms to attract the widest range of pollinators.

If using pesticides in the lawn is unadvisable, it stands to reason that the same would hold true for perennial beds.  Occasionally a pest will move it that needs to be treated.  However, a strong stream of water, hand picking, or other non-toxic method might suffice. Always choose to limit the use of pesticides that will also kill pollinators along with the undesirable pest. Organic methods are not necessarily better; they will kill pollinators just as easily as chemical pesticides.  When necessary to use a pesticide, spot treat and use for the shortest period of time possible.

Happy Gardening

Carol Shirk

Certified Master Gardener