Summertime in Southeast Michigan is a tough season for cool-season grasses like Kentucky bluegrass, perennial ryegrass, and fine fescues. These grasses thrive in spring and fall, but struggle during the hot, dry months of July and August. Fortunately, how you mow your lawn can dramatically impact its health, resilience, and appearance during these peak heat periods.
In this blog, we’ll walk through the essential mowing techniques for hot Southeast Michigan summers—covering mowing height, blade sharpness, frequency, and how to safely sharpen your mower blades.
Why Mowing Matters More in the Heat
Heat and humidity in Michigan can stress your lawn in a matter of days. Mowing incorrectly—either too short or with dull blades—can make things worse by:
- Exposing roots to sun and heat.
- Slowing growth and inviting weed invasion.
- Increasing water loss from the soil.
- Making your lawn more prone to disease and pests.
By contrast, proper mowing helps:
- Insulate the soil from sun exposure.
- Promote deep, drought-resistant root systems.
- Maintain a thick canopy that blocks weeds.
- Keep your lawn looking green, lush, and even.
Mowing Height: Go High in July
The most important summer mowing tip is this: raise your mowing height. For Southeast Michigan’s cool-season grasses, that means keeping your grass between 3.5 and 4.5 inches tall during summer months.
Why Mowing Taller Helps
- Shades the soil to reduce evaporation.
- Encourages deeper roots, which can access water below the surface.
- Reduces heat stress, especially during July and August when temperatures regularly top 85°F.
- Helps crowd out weeds by increasing canopy density.
Pro tip: Check your mower’s manual or measure the height by parking it on a flat surface and measuring from the ground to the blade.
Mowing Frequency: Follow the 1/3 Rule
Never remove more than ⅓ of the grass blade at one time. If your lawn is 4.5 inches tall, only cut it down to about 3 inches. Removing too much of the blade at once can shock the grass, weaken the root system, and leave it vulnerable to pests, disease, or drought.
In Summer:
- Mow once every 5–7 days, depending on rainfall and growth.
- Mow more frequently after a rainstorm or watering.
- Avoid mowing during midday heat—early morning or late afternoon is best.
Sharp Blades = Healthier Grass
Mower blade sharpness is one of the most overlooked lawn care essentials. A dull blade doesn’t cut—it tears. Torn grass tips turn brown and make your lawn look dry and patchy, even if it's getting enough water.
Signs of a Dull Blade:
- Grass tips look frayed or shredded.
- Lawn appears brown or yellow after mowing.
- Uneven cutting or streaks across the yard.
- Increased fuel use or strain on electric motors.
Benefits of Sharp Blades:
- Cleaner cuts that heal faster.
- Greener appearance and better drought tolerance.
- More efficient mowing (less resistance, quicker cuts).
- Healthier grass that's less prone to fungal infections.
How Often Should You Sharpen Mower Blades?
As a general rule of thumb:
- Sharpen every 20–25 hours of mowing.
- For most homeowners, this means 2–3 times per mowing season.
- Sharpen immediately if you hit rocks, sticks, or thick debris.
How to Sharpen Mower Blades Safely: Step-by-Step
Sharpening your mower blades is a simple DIY task, but it must be done carefully to avoid injury or damaging your equipment.
Tools You’ll Need:
- Safety gloves and goggles
- Wrench or socket set
- Blade file or angle grinder
- Blade balancer or nail in a wall
- Wire brush
Step-by-Step Guide:
1. Disconnect the Power
- If it’s a gas mower, remove the spark plug wire.
- For battery-powered mowers, remove the battery.
This is crucial to prevent accidental starts.
2. Tip the Mower Safely
- Tilt the mower with the air filter and carburetor facing up to prevent oil leaks.
3. Mark the Blade
- Use chalk or a marker to mark the bottom side of the blade. This helps ensure you reinstall it correctly.
4. Remove the Blade
- Use a wrench or socket to loosen the blade bolt.
- Secure the blade with a block of wood if it moves.
5. Clean the Blade
- Use a wire brush to remove dirt, rust, and grass buildup.
6. Sharpen the Blade
- Use a metal file or an angle grinder to sharpen the edge to about a 45-degree angle.
- File in one direction, matching the existing bevel. Remove just enough metal to restore a clean edge.
7. Balance the Blade
- Use a blade balancer or place the center hole on a nail in a wall. The blade should stay level. If one side dips, file more from that side.
8. Reinstall the Blade
- Reattach the blade in the same orientation you removed it.
- Tighten the bolt securely and reconnect the spark plug or battery.
Blade Sharpening Safety Tips
- Wear gloves to prevent cuts.
- Always disconnect power before working on a mower.
- Use a clamp or vise to hold the blade steady during sharpening.
- Don’t over-sharpen—razor-sharp blades can chip easily on rocks.
Extra Summer Mowing Tips
- Mow with sharp blades only and replace them every 1–2 seasons if they’re worn or chipped.
- Leave the clippings unless they clump. Grass clippings return moisture and nitrogen to the soil.
- Avoid mowing wet grass to reduce clumping and mower strain.
- Alternate your mowing pattern each time to prevent soil compaction and ruts.
Summary: The Southeast Michigan Summer Mowing Checklist
