Are you familiar with the lazy man’s method of lawn care? In this low-maintenance approach, you only mow when you need to find where you left the wheelbarrow. However, most homeowners appreciate a more manicured approach to lawn care.
Lawns help create a healthier atmosphere in exchange for the care we give. They produce oxygen, filter harmful pollutants that run off hard surfaces and cool the surroundings, to name a few benefits.
There are legitimate reasons for maintaining a healthy lawn. Lawn care has evolved in the past decades, and many of the old ways of doing things aren’t the best for our lawns.
Science reveals things we didn’t always realize. For example, remember when everyone fertilized in early spring “to get the grass to green up?” Well, force-feeding the lawn before the grass needs the nutrition has been shown to be counterproductive.
The science behind the healthiest lawn is quite simple: Understand that grass follows a definite natural seasonal growth cycle, and then mesh lawn care into that natural rhythm. If our practices go opposite the cycle, grass can be diminished.
The grasses that comprise lawns in North Dakota and Minnesota are generically termed cool season grasses, as opposed to the warm season grasses of the Southern states. The geographic zone between cool and warm season grass is an area in the country’s midsection where growing grass is difficult, nicknamed the “Crabgrass Belt.”
In the natural cycle of our cool season grass, growth is rapid during spring and fall when temperatures are cool and moisture is plentiful. Grass becomes less active, or even dormant, during the heat and possible drought of midsummer. The main triggers are not only moisture but temperature. A sustainable lawn care routine should support this natural life cycle.
In spring, grass roots are long and full of nutrients stored from the previous fall. Grass shoots use this stored growth for rapid spring growth. When hot summer temperatures arrive, leaf and root growth slows, as grass rests during heat and the dryness that often accompanies it. Roots can be damaged if soil temperatures rise above 85 degrees.
In fall, grass shoots resume strong growth, storing energy and nutrients in the long, active roots in preparation for winter. The best shoot growth occurs with air temperatures between 55 and 75 degrees.
The following recommendations mesh lawn care with grass’s natural cycle, for most effective results.
Lawn care calendar
• Seeding: Aug. 15 to Sept. 15. Secondary time: May through early June.
• Fertilizing: Labor Day through mid-October. Secondary time: Memorial Day through June.
• Core aerating: Aug. 15 through Oct. 15. Secondary time: May.
• Dethatching (power raking): Aug. 15 through Sept. 30. Secondary time: May 15 through June 15.
• Broadleaf weed control: September. Secondary time: May through June.
• Crabgrass control: For pre-emergent herbicide (applied before weeds appear) mid-April after soil warms to 50 degrees.
For post-emergent herbicide (applied to very small, visible crabgrass), May through June.
Lawn care don’ts
• Don’t fertilize too early in spring. It encourages grass to grow during a time it should be slow or dormant. It’s best to wait until closer to late May.
• Don’t fertilize in the hot midsummer months. It can cause irreversible damage to grass plants.
• Don’t spray to control weeds when temperatures are warm, which increases likelihood of damage to lawns.
• Don’t mow lawns short. Instead, increase mowing height to 3 inches.
• Don’t water with frequent, light sprinklings, which cause shallow roots. Instead, water once a week, applying 1 inch in the absence of rain, or divide between two waterings on light, sandy soil.