While you may be tempted to keep your grass-cutting height low in order to reduce the number of times you have to go out and mow in the blistering sun, this can actually hurt more than it helps. One of the most frequent questions we get asked relating to grass cutting is at what height to cut grass in the summer. Or more specifically, “Why Keep Grass at 3 Inches?”.
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Should I Cut My Grass to 3 Inches?
While there can be some variation in mowing heights depending on grass type, research generally shows that dense grass that is 3 inches tall (or taller) is typically healthier than grass at shorter heights. This is due to the taller blades shading the soil below, preserving naturally-occurring moisture and keeping sunlight from reaching weed seeds and allowing them to germinate.
If you cut your grass too short, you encourage shallower roots. This in turn makes it tougher for your roots to access natural moisture and nutrients that are found in your soil. Not only that, cutting your grass shorter than 3 inches allows light to get to weed seeds sitting on top of the soil, which can lead to crabgrass infestations or worse.
What Are the Other Benefits of Cutting Your Lawn at 3 Inches?
In addition to preserving moisture in the soil and reducing the amount of weeds that can germinate, keeping the grass a 3 inches actually has multiple other benefits. These benefits include:
- Taller grass (3 inches or more) typically grows more slowly than shorter grass – Because of how plants photosynthesize light into energy, longer blades of grass have more surface area to work with. This means it doesn’t need to grow as fast to maintain itself.
- Taller grass doesn’t require as much fertilizer – Because of the more efficient energy collection that is done by longer blades of grass, the lawn provides for itself better when it comes to producing food. This means that you may need less fertilizer to get the grass that lush green color you are always striving for.
- Longer grass reduces the amount of landscape watering needed – In addition to longer blades of grass being more efficient in collecting energy, they typically have longer roots and can access water stored farther down in the soil.
- 3+ inch tall grass reduces insects and disease – Longer grass is indicative of healthier grass, which means it will naturally be able to resist disease. It can also be a more inviting habitat for insects that would keep out the pests in the area.
Is It Better to Keep Grass Long During Extreme Heat?
As a general rule, keeping your grass longer during the heat of summer can help to protect your grass and keep out unruly weeds. In fact, during hotter periods you may consider cutting your grass to a height of 4 inches (or longer). This can provide maximum resistance to your lawn drying out and allowing in weeds.
How Tall or Short Should I Keep My Grass In the Winter?
If you’re wondering what is the best height to cut your grass for winter, a good rule of thumb is to lower your mower height by one notch so the grass is about 2.5-3 inches long. This can help to prevent winter problems like pests while still protecting the roots.
Keep Your Grass at Three Inches For Best Results
As you can see, keeping grass at a height of 3 inches or more can be beneficial for the grass AND may even reduce the amount of times you mow your lawn! As your lawn starts to approach fall, you may also want to consider a fall nitrogen blitz for your lawn to get it ready for the coming spring season.
If you have any questions, comments or tidbits you’d like to share about lawn-cutting heights, leave them in the comments below!