Kentucky Bluegrass Spring Lawn Care
Timothy Newcomb, Anoka County Extension Master Gardener
April in Minnesota is normally marked by the final stages of winter receding. This year was different, and rather than dealing with snow, we’ve been stuck looking at mostly brown mats of grass left over from last year. Even with this unusual winter, our lawns will perk up as rain and warmth return to our region. As soon as our grass starts growing, the annual work of taking care of our lawns begins.
Most Minnesota lawns are a combination of grasses, with Kentucky bluegrass being the primary grass, and the rest being a mix of perennial ryegrass and fescues. When well maintained, these grasses provide the green-carpet-looking lawns that we desire.
Kentucky bluegrass is a cool-season turf grass that grows in the spring and fall. It is popular in Minnesota because it is well adapted to cooler climates. It spreads out by rhizomes and can fill in damaged areas, allowing your lawn to repair itself over time. It is also disease resistant, able to handle foot traffic, and drought tolerant during cooler months.
Unfortunately, Kentucky bluegrass has some drawbacks. It doesn’t do well in shade, it turns brown in excessive heat, and it is a heavy feeder. It can also develop thick layers of thatch and dense roots that make the soil impermeable. While these problems are solvable, maintaining a beautiful, healthy lawn can require time, effort, and resources.
Here are some tips for caring for your bluegrass this spring:
Raking: Avoid raking until the ground has thawed and your grass turns green and starts to grow. Raking too early can damage your grass.
Watering: Water your lawn every few days in the early morning, ensuring it receives about one inch of water per week. Kentucky bluegrass has a shallow root structure, so checking the moisture in the top few inches of soil can help you tell when to water.
Mowing: Mow when your grass is approximately 4.5 inches tall, taking it back to 3 inches. Don’t cut off more than one-third of the length at any one time. Mulch grass clippings back into your yard to improve soil health and reduce water and fertilizing needs.
Dethatching: While half an inch of thatch can be beneficial for keeping out weeds and keeping in moisture, more than that can create problems. Dethatch in the spring as needed.
Aerating: If your yard has become compacted and water is no long getting through, spring is the time to aerate.
Fertilizing: Fertilize your lawn when it is actively growing in the spring and fall. A soil test will assess your lawn’s current conditions and offer specific recommendations for improvement.
During periods of heat and drought, increase your mower height to 4 inches to provide extra protection from sun and evaporation. Also limit mowing, foot traffic, and chemical applications including fertilizer.
With the proper care, your Kentucky bluegrass can get a healthy start this spring.
For more lawn care tips, check out https://extension.umn.edu/lawns-and-landscapes/lawn-care or go to https://extension.umn.edu/ and search ‘lawns.’