Quick Answers
There are pros and cons to both keeping grass long and keeping it short in summer. Some key factors to consider are:
- Long grass shades the soil and helps retain moisture, reducing water needs.
- Long grass can insulate the soil and protect grass roots from heat stress.
- Short grass may be more aesthetically pleasing for some.
- Short grass allows for thicker growth and requires less mowing.
- Long grass can harbor more pests like ticks.
- Long grass may require more watering in very hot/dry climates.
There is no definitive “right” answer, as the best grass length depends on climate, grass type, water availability, and personal preference. In moderate summer climates, longer grass 3-4 inches may provide benefits. But in very hot/dry climates, shorter 1-2 inch grass may fare better.
The Benefits of Longer Grass in Summer
During the hot summer months, there are some compelling reasons why you may want to let your grass grow a little longer than usual:
Longer Grass Shades the Soil
One of the biggest benefits of longer grass is that it helps create a shady canopy over the soil. Instead of intense sunlight beating directly down onto the ground, longer blades provide protective coverage. This shade helps the soil retain more moisture rather than drying out quickly in the heat.
Longer Grass Insulates the Soil
In addition to the shade benefits, having longer grass helps insulate your lawn’s soil from extreme temperatures. Bare soil can get scorching hot in the sun. But a lush 3-4 inch lawn acts as a temperature buffer between the soil and hot ambient air. This helps moderate soil temperature, protecting grass roots from heat damage.
Longer Grass Means Less Watering
By keeping soil cooler and moister, maintaining longer grass heights in summer means you may not have to water as often. The shading and insulation benefits reduce soil moisture evaporation. And longer roots can access deeper water reserves. This can lead to substantial water savings compared to trying to keep a very short lawn green during hot, dry weather.
Longer Grass Leads to Stronger Grass Plants
Letting your grass grow longer encourages the plants to grow deeper roots. Short grass is more likely to have shallow root systems. But longer grass blades signal to the plant to extend its roots further down into the soil profile, where more moisture is available. These deeper roots make the grass more drought-resistant during summer dry spells.
Less Need for Fertilizer
Longer grass also needs less fertilizer. It grows more slowly, so nutrients are utilized efficiently. Short grass often demands heavy fertilization to sustain its rapid growth habit and maintain thickness. But longer grass can get by with less fertilizer, saving you money.
Potential Downsides of Long Grass
While longer summer grass offers many benefits, there are also some potential downsides:
Increased Pest Habitat
If allowed to get excessively long, thicker grass can shelter more pests. Rodents may find it a good place to hide and build nests. And longer grass can harbor more ticks looking to latch onto pets or humans. Keeping growth under 4 inches reduces this concern.
More Clippings When Mowing
You will need to mow less frequently with longer grass. But when you do mow, the clippings volume will likely be greater. This can lead to clumping or visible clippings left on the lawn unless you have a powerful mower and mulch or bag the cutting debris.
Potential Messy Look
Some people simply think longer grass looks untidy, messy, or unkempt. Although others think it looks lush and healthy. It’s a matter of personal preference.
May Still Need Watering in Extreme Heat
While longer grass holds up better in summer and needs less water overall, it may still require supplemental irrigation during periods of extreme heat stress without rain. If temperatures are hot enough, even longer grass will go dormant without sufficient soil moisture.
Advantages of a Shorter Summer Lawn
If you prefer to keep your lawn on the shorter side in summer, there are some advantages to doing so:
Can Withstand Heavy Use
Shorter grass is better able to tolerate heavy foot traffic, play activity, and other wear and tear. Longer blades are easier to damage or crush down, leaving unsightly paths.
Less Pest Habitat
As mentioned earlier, very long grass can shelter more rodents and ticks. Keeping your lawn trimmed to 1-2.5 inches minimizes the potential for these pests to become established.
Thicker Growth Habit
Repeatedly mowing your grass short encourages dense, thick turf growth. This creates an attractive carpet-like lawn appearance that many desire. Longer grass grows more sparsely.
No Clumping of Clippings
With very short grass, mowing clippings are tiny and decompose rapidly. They easily filter down to the soil surface without clumping on top of the blades. Short clippings are virtually invisible.
May Require Less Watering
In climates with extremely hot summers, shorter grass may actually require less water than taller growth. The reason is less foliage leads to less transpiration water loss. As long as the soil is shaded by surrounding trees or buildings, short grass can sometimes get by with less irrigation.
Easier Weed Control
Keeping grass clipped to a short height allows you to more easily spot any weed invaders. Weeds stand out against the uniform turf. You can then hand pull the weeds or use selective herbicides. Weeds can hide more easily in taller grass.
Potential Problems with Very Short Summer Grass
However, maintaining an extremely short lawn in the summer also has some potential drawbacks:
Increased Water Demand
Lack of shade for the soil means it will dry out faster. This can significantly increase landscape irrigation requirements compared to longer grass that holds moisture better. Watering needs can escalate quickly during hot spells.
Weak Root System
Without the need to grow deeper roots to find moisture, short grass often develops shallow roots. This makes it more vulnerable to heat stress and drought die-off.
Higher Fertilizer Demand
The rapid growth habit of short grass requires more fertilization to look its best. Fast top growth means more nutrient depletion that has to be replaced.
Increased Weed Pressure
Short grass with open soil is prime real estate for weeds to germinate and get established. Crabgrass in particular thrives in closely mowed summer lawns. Greater weed control efforts are needed.
More Frequent Mowing
Keeping your lawn very short usually means having to mow more than once a week during the peak growing months. This takes more time and labor compared to maintaining longer grass.
Best Overall Summer Grass Length
When weighing the pros and cons, a happy medium grass length of around 3-4 inches is a good compromise for most regions in summer. Here are some of the benefits of keeping grass in this height range when temperatures climb:
- Provides reasonable shade for soil without excessively blocking sun
- Moderates soil temperatures by insulating the ground
- Encourages deep root growth for drought tolerance
- Reduces – but doesn’t eliminate – mowing frequency
- Minimizes weed competition compared to very long grass
- Maintains a tidy, uniform appearance
- Lessens pest habitat versus very long grass
- Cuts down on watering needs by preserving soil moisture
The following table summarizes the key pros and cons of different summer grass heights:
| Grass Height | Pros | Cons |
|---|---|---|
| Very short (1-2 in) | Withstands heavy traffic No clumping of clippings Lower water needs in some climates Easier to spot weeds |
Can dry out soil quickly Weak roots High fertilizer needs More frequent mowing Higher weed pressure |
| Moderate (3-4 in) | Good soil shade/insulation Encourages deep roots Reduces mowing Lessens weed competition Lower water needs Neat appearance |
May harbor some pests Messy look for some |
| Very long (4+ in) | Maximizes soil moisture retention Stronger grass plants Least mowing Lower fertilizer requirements |
Can get untidy look Clumping of clippings when mowing Increases pest habitat |
Grass Length Tips for Different Climates
While a 3-4 inch summer grass height works well for most regions, some adjustments based on climate may optimize results:
Hot and Dry Climates
In extremely hot, arid regions, consider keeping grass slightly shorter at 1.5-3 inches. This reduces water demands a bit. But avoid mowing lower than 1.5 inches to prevent heat/drought stress.
Cool and Wet Climates
Where summers are mild and ample rainfall is expected, let grass grow up to 4 inches tall. Maximize the shading and insulating benefits where moisture is abundant.
Transitional Weather Climates
In regions where summer brings a mix wet and dry periods, adjust mowing height accordingly. For example, let grass grow longer leading up to expected dry spells. Then trim it shorter after sufficient rainfall returns.
Coastal Climates
Near coastal areas, moisture is typically adequate to support slightly longer grass. But salt spray and wind may dictate keeping growth under 4 inches to avoid excessive damage.
Best Grass Species for Longer Summer Lengths
Certain grass types adapt better to longer summer heights than others. Top-performing varieties include:
Tall Fescue
A deep-rooted cool season grass that tolerates summer heat well at longer lengths.
St. Augustinegrass
A warm season variety often maintained taller in southern lawns.
Buffalograss
A drought-tolerant warm season grass very compatible with infrequent summer mowing.
Centipedegrass
Another low-maintenance warm season type suited for longer summer lengths.
Bermudagrass
Tolerates both heat and moderate shade, making it ideal for longer summer growth.
Zoysiagrass
Thrives during heat if kept taller and retains good density.
Ryegrass, bentgrass and fine fescues are cool season types less compatible with very tall summer heights that invite disease and weak growth. Kentucky bluegrass can work if water is sufficient.
Tips for Managing Longer Summer Grass
To get the most out of increasing your mowing height in summer, keep these lawn care tips in mind:
- Raise cutting height gradually as temperatures climb rather than all at once.
- Sharpen mower blades regularly for clean cuts that heal quickly.
- Water deeply but infrequently to encourage deeper roots.
- Apply slow release fertilizer at the start of summer to fuel growth.
- Monitor for pest problems and treat promptly if needed.
- Adjust height down again gradually as cooler weather returns.
Conclusion
Deciding whether to keep your lawn longer or shorter during the hot summer months depends on a variety of factors. But in general, allowing grass to grow a bit taller around 3-4 inches offers a number of benefits. The additional length shades and insulates the soil, reduces watering demands, minimizes weeds and pests, and protects grass plants from heat stress. Yet is still short enough to maintain a reasonably tidy appearance without excess mowing or irrigation requirements. Adjusting cutting height according to your local climate, grass type and maintenance preferences will ensure your lawn thrives through the summer.
