By allowing your grass to grow longer, your grass will develop stronger roots, which leads to better drought resistance and lower watering needs. You’ll also save money by mowing less frequently. Not only will you use less gas for mowing, but you also won’t need to fertilize your lawn as often if you let it grow long. This is because taller grass gathers more energy from the sun, which means it needs less frequent fertilizer applications. As added bonuses, taller grass helps to stop low-growing weeds like crabgrass and encourages the growth of wildflowers that essential pollinators feed on. For greener grass in the summer, reduce your mowing to once every 1–2 weeks, or less during hot spells.
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How Long Should You Let Your Grass Grow?
Let upright species of grass grow to a length of 3.5 to 4 inches (9–10 cm). Grasses that benefit from growing at this height include Kentucky Bluegrass, Ryegrass, Fescue, Centipede grass, and St. Augustine. These grasses will grow very lush at these taller heights. This results in a thicker, greener lawn. Common practices that call for mowing these grasses to 2.5 inches (6 cm) or lower contribute to weaker grass, dry soil, and more weeds.
- Tall or “upright” grasses can be allowed to grow up to 4 inches (10 cm) long.
- Upright grasses include Centipede grass, Fescue, Kentucky Bluegrass, Ryegrass, and St. Augustine grass.
- Creeping grasses can be allowed to grow as long as 2.5 inches (6 cm).
- Bermuda grass and Zoysia are common examples of creeping grass.
If your lawn is a creeping grass variety, such as Bermuda Grass or Zoysia, allow it to grow to a height of 2.5 inches (6 cm). This may still seem short, but in some cases, these grasses are mowed as short as 1 inch (2.5 cm). Allowing these grasses to grow longer helps them spread, gather more light, and fill in bare spots of your lawn.
What are the Benefits of Letting Grass Grow Long? [7 Bonuses]
Allowing grass to grow long results in a lush lawn with less maintenance. In fact, in many areas “No Mow May” has caught on as a way to preserve local wildlife and produce a healthier lawn. Here are some shocking upsides of letting your lawn grow longer:
Stronger Grass Roots
If your grass is allowed to grow longer, it will be able to expend more energy to produce deeper roots. With the increased area of the longer grass blades, the grass plants are able to gather more energy from the sun. This leads to stronger plants that grow deeper roots. These deeper roots contribute to increased nutrient uptake and better drought resistance for your yard. So, if you want a healthier lawn, let it grow long.
Water Less Frequently
By allowing your grass to grow long, you’ll reduce the watering needs for your lawn. Longer grass blades provide shade for the soil surface. This keeps the upper layers of soil moist and allows more water to penetrate your grass roots. Cutting your lawn short exposes the soil surface to sunlight, which evaporates water and dries out the soil quickly. If you mow your lawn short, you’ll need to water more often to keep your lawn alive.
Less Fertilizer Required
Remember how longer grass blade growth encourages deeper roots? This means that your grass will pull more nutrients from the soil, so your lawn can get more out of fertilizer. Mowing at a taller blade height allows you to grow a greener lawn with fewer yearly fertilizer applications. Not only that, but the increased blade length means your grass can gather more energy from photosynthesis, reducing your lawn’s dependency on soil nutrients.
The less frequently you mow, the more you’ll save on gas or electricity (depending on your mower’s power source). By switching to twice-monthly mowing cadence you’ll cut back on fuel costs. Add in the money you save by watering and fertilizing less often and growing a longer lawn can put hundreds of dollars back in your pocket each year.
Low-growing weeds like crabgrass and clover are choked out by tall grass. As these weeds attempt to sprout near the soil surface, the tall grass blades block the light. This means you’ll get fewer tufts of crabgrass and other pest grasses if you let your lawn grow taller. This can save you from spraying for weeds or using crabgrass preventer in spring.
Encourage Wildflowers and Pollinators
Although tall grass will often stop invasive grasses, it will encourage the growth of wildflowers, such as wild violets and dandelions. Although these may seem like weeds to you, they are an essential food source for bees, butterflies, and other pollinating insects. These insect species are increasingly threatened. Letting your lawn grow tall invites pollinators and helps to protect the environment.
Prevent Brown Summer Grass
It is a great idea to let your lawn grow longer in summer to prevent brown patches of grass. Mowing during high heat, especially during dry weather, puts extra stress on your lawn. This causes your grass to turn brown after mowing. If your lawn’s growth slows during the peak of summer, you can hold off on mowing for 4–6 weeks. Once it does get too long, just make sure to mow at the right time of day to prevent stressing your grass.
Does Tall Grass Attract More Bugs?
Very tall grass can attract more bugs, including gnats, mosquitos, and ticks. However, this typically only becomes a problem when grass is longer than 6 inches (15 cm). If you mow your grass when it reaches 5 inches (13 cm) in height, you’ll avoid the worst pests in your lawn.
- Tall grass does attract more insects.
- Pest insect infestations typically are at their worst when grass grows over 6 inches (15 cm) in height.
- Taller grass can also attract beneficial insects, including butterflies, bees, ladybugs, grasshoppers, and praying mantises.
An upside of tall grass attracting bugs is that you will see more butterflies, bees, and other beneficial insects in your lawn. These beneficial bugs are harmless to humans and great for the environment. Plus, many of them eat pest bugs. So, by keeping your grass under 6 inches, you’ll get several benefits without attracting harmful bugs.
Is it OK to Let Grass Go to Seed?
Do not let your grass grow long enough to produce seeds. Once a grass plant begins producing seeds, it will focus its energy on this task. This means the grass will put less energy into producing strong roots and spreading to fill in bare spots of your lawn. If your grass has grown tall enough to produce seed heads, it’s time to mow.
- It’s best to mow grass instead of letting it go to seed.
- Grass that goes to seed may put less energy into developing strong roots and thick growth.
- Mow grass once you see the first seed heads appear.
Different grass varieties produce seeds at different heights and at different times of the year. Keep an eye on your lawn as you allow it to grow longer. Once you see seed heads waving in the breeze, it’s time to rein in the grass.
Is it Better to Keep Grass Long or Short in Summer?
There are some incredible advantages to letting your grass grow longer in the summer. The top reasons to consider mowing at a higher blade height are:
- Your lawn will develop stronger roots, which makes your grass more resilient.
- Long grass requires less frequent watering, since tall grass blades protect soil moisture from evaporation.
- A longer lawn can grow healthy with less frequent fertilizer applications.
- Mowing less frequently will save money on gas, as well as reduce spending on watering and fertilizer.
- Tall grass helps to choke out ground-covering weeds like crabgrass and invasive clover.
- Wildflowers will grow in tall grass, which helps support local butterfly and bee populations.
- Mowing less often and at a taller height helps stop grass from turning brown during heatwaves.
In order to get these benefits, let your grass grow 1–2 inches (5–10 cm) taller than you usually would. Additionally, when grass growth slows in extreme heat, put a pause on mowing. This will contribute to a healthier lawn with less maintenance.