Slow Mow May

What is Slow Mow May?

Don’t spring into mowing too fast! For pollinators’ sakes, the Village wants you to take it slow for Slow Mow May by mowing less frequently (once every 2-3 weeks) this springtime. 

In our area, pollinators start to emerge in early May. They rely on flower nectar and pollen for food, but floral blooms are scarce at this time. With reduced lawn-cutting, you are creating habitat and forage for the beneficial insects that desperately need our help due to the concerning trend of pollinator decline.

In 2023 from May 1 to June 1, the Village of Northbrook is suspending enforcement of the Municipal Code for excessive grass height and is encouraging all community members to participate in our "Slow Mow" initiative to voluntarily decrease mowing in support of wildlife. This may result in ground-cover exceeding the established ordinance height restrictions of eight inches, which is why enforcement is suspended for May for registered participants.

How Can I Participate?

This year, community members are required to register to participate in Slow Mow May. There are two ways to register:

1. Email with your property address.

2. Starting May 1, register in-person with the Development and Planning Services Department (second floor of Village Hall, 1225 Cedar Lane). To receive a “Slow Mow May” yard sign, you must register in-person.

Slow Mow May Sign

Please note we are providing the signs only, garden stakes and zip ties are not provided.

“Slow Mow” vs. “No Mow”… What’s the Difference?

Last year, the Village participated in No Mow May, which is an international movement that discourages mowing for the entire month. Following review of the public comments received and further study of the research regarding pollinators and lawncare, the Sustainability Commission made the alternative recommendation in support of Slow Mow May. 

To support pollinators, cutting your lawn once every 2-3 weeks is recommended. This is thought to be a middle ground where spring flowers can bloom, but grass is short enough that it is still navigable for insects to locate the flowers for food.

Registration will be required to participate. Enforcement of the grass height ordinance is waived until June 1 only for those who register.

Common Blue Violet and Dandelions

What Grows When You Don't Mow?

When May lawn-cutting is delayed in Northbrook, you may find clover or common blue violets flowering in your yard. Our native bees rely on spring blooms for food and energy to start their colonies for the season. As scientists urge that the decline in insect populations is a concern for biodiversity, your yard can make a difference to help the survival of endangered species like the rusty-patch bumblebee!

Why Should I Help Pollinators?

Scientists project that the world loses 2.5% of insect mass per year. Pollinator decline refers to the reduction in populations of pollinating animals such as bees, butterflies, and birds, which are responsible for transferring pollen thereby facilitating reproduction of plants. This decline has been observed globally over the past few decades, and is alarming because pollinators play a critical role in maintaining the diversity and productivity of ecosystems, as well as the production of many crops that are important for food security.

Does This Really Help Pollinators?

Mowing your lawn less frequently allows pollinators to safely emerge and early-flowering plants to grow. The opportunity to establish beneficial insect populations (like our native bumblebees) is drastically reduced with early spring leaf litter removal and weekly grass mowing. However, a mere reduction in lawn-mowing is not the end-all be-all of supporting our local ecology. 

The typical suburban landscape is considered a monoculture dominated by a single species or a few species of non-native plants, such as Kentucky bluegrass or Bermuda grass. Our native wildlife rely on plant species they co-evolved with for successful nutrition and habitat, so planting native supports the overall ecosystem. (Note: Northbrook’s grass height ordinance only applies to non-native grasses. Native grasses like bluestem, sedges, and ryes may grow to any height unless they are planted in an area that could interfere with visibility of motorists).

Beyond reduced mowing, much can be done in support of pollinators on all or a portion of your yard:

  • Incorporate a range of native plants with a succession of bloom times to provide floral resources spring through fall. Some great choices are bee balm, foxglove, and goldenrod.
  • Commit to low or no use of pesticides, which can kill or weaken pollinators’ ability to reproduce.
  • Leave fallen tree leaves and dried-up vegetation for birds and nesting insects like dragonflies and butterfly chrysalises.