No-Mow May or Slow-Mow Summer?

History of No-Mow May

The No-Mow May movement was started by a non-profit organization, Plantlife (1), based out of Great Britain, in 2019. The movement was popularized in the United States with help from the city of Appleton, Wisconsin (a couple of hours from where I live in Central Wisconsin) and Lawrence University, also in Appleton (2). Appleton and Lawrence are associated with an initiative of the Xerces Society, Bee City, and Bee Campus (3). The Xerxes Society is a nonprofit organization focused on saving insect habitats and thereby the insects themselves. The first No-Mow May campaign began in Appleton and the surrounding Fox Cities area in 2020. Due to its catchy name and, I think, many people’s desire to make a difference in the environment, the movement quickly caught on. The point of No-Mow May is, logically, to not mow your yard in May (in more southern locations No-Mow April makes more sense) to increase the number of flowers for bees to forage, particularly early in the spring when food is limited.

Does No-Mow May Make a Difference?

​The short answer is, it depends. If you have a perfectly manicured lawn with no flowers (what many people consider weeds in lawns) then allowing your grass to grow tall is not helpful (4). If on the other hand, you have many different flowering plants (especially natives) growing in your lawn, it could make a difference. However, what flowers you have growing in your lawn is what matters. Many lawns that are not treated with herbicides tend to grow dandelions and Creeping Charlie. While some bees will visit these flowers, they are not the best source of nutrition for bees. Creeping Charlie is invasive in many states and it is not a reliable source of nectar for bees (5). Dandelion pollen has a low protein content (only 15%), which is not sufficient nutrition for bees (6). Ideally, you would plant native flowers in your lawn, in my area violets (Viola sororia), Self-heal (Prunella vulgaris) and Yarrow (Achillea millefolium) do well. Native plants also have an advantage in that they attract native bees (7) (honeybees are not native to the United States). Dutch white clover (Trifolium repens) is a good bee food since it has high protein content in the pollen and high sugar content in the nectar and does great in lawns, although Dutch white clover is not native (7). Creeping thyme (Thymus praecox) is also often included in lawn bee mixes, although it is also not native, because it is low-growing and a good source of nectar (7).  For me, the best part about No-Mow May is that it is a gateway for many people to learn about why all insects are important (bird food!), not just bees, and how to add and improve insect habitat on their own properties (2).

Slow-Mow Summer

​Slow-Mow Summer is an alternative to No-Mow May. Similar movements are called Slow-Mow Spring, Low-Mow Spring, and Low-Mow Summer. These movements are closer to the ideal of helping native insects for a longer time than just one month. If you do decide to plant native flowers for bees to forage, not mowing only one month out of the year does not help as much as it could. Ideally, you would mow less often and mow higher (about 4”), allowing your native (or partially native) ground cover a chance to flower between mowings (8-10). 

Dutch white clover (left), while not native is a good food for bees. Purple self-heal (Prunella) flowers and yarrow (ferny-type plant) are both native flowers that adapt well to lawns.

Why do Lawns Matter?

​It is estimated that up to 40 million acres of land in the United States have been converted into lawns (11). Most lawns are sterile, providing little food for herbivorous insects, which feed the birds, especially baby birds. If rural and suburban homeowners are willing to reduce the size of their lawns, switch some of their laws to bee lawns, and increase native flower plantings (see below), this could make a huge difference in increasing biodiversity in the United States (11).

An Alternative to Slow-Mow Summer

​One alternative to mowing less often is to create flower beds full of native flowers. There is nothing wrong with keeping a lawn, it is great for dogs and kids especially. However, decreasing the size of lawns and increasing native plant beds is a great, probably even better idea, than trying to turn turfgrass into a low-growing flowering bee lawn (11). In conjunction with planting native plants is to not clean up your flower beds in the fall (#LeaveTheLeaves) and delay clean-up until late spring. Or at the very least trim your beds and let the dead stalks hang out nearby along with any leaves until spring. Many native insects overwinter in dead plant debris and leaves and many birds feast on dead seed heads all winter.

Conclusion

Whether you choose to plant a bee lawn, reduce or eliminate pesticide usage, add native plants to your flower beds, reduce the size of your lawn, or whatever combination works for you and your property, the important thing is to make a change and bring awareness to the issue of declining pollinators and insects in general. I have listed many resources below if you are interested in reading further. The University of Minnesota Bee Lab also has a list of companies that sell bee lawn mixes if you wish to change some of your lawn to a bee lawn (12). Alternatively, there are several native plant nurseries, such as Prairie Moon Nursery in Minnesota (13) and Prairie Nursery in Wisconsin (14) that sell native seeds and plants online.

References and Resources

1. Plantlife. https://www.plantlife.org.uk/
2. No Mow May: A Gateway to Better Landscape Management for Bees. https://www.xerces.org/blog/no-mow-may-gateway-to-better-landscape-management-for-bees#:~:text=No%20Mow%20May%20began%20in,weather%2C%20vegetation%2C%20and%20people.
3. Bee City USA. An Initiative of the Xerces Society. https://beecityusa.org/
4. Day, H. G, Gratton, C., Hill, J., Koch, P. Krokowski, K. Liesch, P. J., Potratz, M., Renz, M., Ripp T., and Soldat, D. What’s the Deal with “No Mow May?” Wisconsin Horticulture Division of Extension. https://hort.extension.wisc.edu/articles/whats-the-deal-with-no-mow-may/
5. Wolfin, J. and Koenig, P. Creeping Charlie: Management and Value to Pollinators. University of Minnesota. Turfgrass Science. 2017.
6. Holm, Heather. Saving Our Bees. 2019. https://neighborhoodgreening.org/saving-our-bees-by-heather-holm/
7. Moncada, K. and Wolfin, J. Planting and Maintaining A Bee Lawn. University of Minnesota Extension. 2023. https://extension.umn.edu/landscape-design/planting-and-maintaining-bee-lawn#flowers-for-bee-lawns-2939361
8. No Mow May, Slow Mow Spring. Bee City USA. https://beecityusa.org/no-mow-may/
9. No Mow, Slow Mow 2024: FAQs. https://beecityusa.org/no-mow-slow-mow-2024-faqs/
10. University of Minnesota. Bee Lab. Slow Mow Summer And Why No Mow Many No Longer Makes the Cut. https://beelab.umn.edu/slow-mow-summer
11. Tallamy, D. W. Bringing Nature Home: How You Can Sustain Wildlife with Native Plants. Timber Press, Portland, Oregon. 2007.
12. Bee Lawn Seed. University of Minnesota. Turfgrass Science. https://turf.umn.edu/lawn-info/purchasing-seed/bee-lawn-seed
13. Prairie Moon Nursery. https://www.prairiemoon.com/
14. Prairie Nursery. https://www.prairienursery.com/