Dry Lawn in the Summer? How to Beat Heat Lawn Stress 

For most of us, summer is not a season of stress. For lawns though, it is. Consistent hot and dry weather over a long period of time can lead to heat or moisture stress, which can cause your lawn to turn brown and even invite a variety of weeds and lawn pests. Heat stress can be compounded if the area you live in is currently experiencing a drought. To keep your lawn at its best and limit the hot summer damage, you should familiarize yourself with some of the basics of this issue.

How Heat Affects Grass

The summer may be a great time to be outside, but the heat affects each blade of grass and especially the roots. Summer heat with bright days, warm nights, and little to no rainfall is the source of many dry lawns during the warm months. When the heat outside increases, the roots beneath the soil shrink in size to reduce the amount of water they need to conserve energy. Sometimes the grass will also utilize its stored energy in the roots to help the plant withstand the intense heat. 

But even with these built-in heat reactions, the grass can still dry out and experience heat stress. Heat stress occurs when the heat gets intense or long, and the grass begins to dry and die because it can’t get enough water. Grass dying in summer heat can happen to all types of grasses, but some are more susceptible than others. Cool season grasses are especially prone to disease and wilting in the summer heat. These types of grasses can experience root damage if soil temperature exceeds 85 degrees. 

Signs of Lawn Stress

On the bright side, heat stress is not that difficult to identify. Early on, your lawn may need a drink if footprints remain on the grass hours after walking on it or if the grass appears discolored (it usually turns gray or a darker shade of green before going brown).

When the effects of stress start to substantially impact your turf, grass blades may curl or turn brown at the tips. If you notice brown patches throughout your yard, this could actually be the result of a variety of different problems (all of which are worsened by drought):

• If the lawn in these areas can be lifted up like a carpet, you may have a grub infestation since these insect larvae eat at the grass roots.
• Push a screwdriver into your lawn. If it becomes difficult and does not go in smoothly, the lawn needs moisture and aeration.
• A brown lawn could also be the result of chinch bugs or other surface feeding insects.

In all of these cases, your lawn will experience great difficulty taking in the nutrients it needs. If you notice any of these signs in your yard during the hot summer months, it would be wise to take precautions against heat stress and prevent your grass dying out or drying out.

Treating Stressed Grass

Once you’ve identified heat stress, it’s time to treat the damaged grass and help it flourish once more. Here are a few tips for how to get those brown spots healthy again: 

• Don’t compact the soil. If your lawn experiences a lot of foot traffic or heavy mowing equipment, your soil will become compacted, and it will be difficult for air to get to the roots. If your lawn suffers from this problem, you’ll need to aerate in order to relieve the stress.
• Water deeply but not often. Watering lightly every day will produce shallow roots that won’t be equipped to handle hot and dry weather very well. Your lawn should receive 1/3 an inch of water every other day in order to remain strong and drought-resistant. Water in the morning to avoid the afternoon’s high evaporation rates and the possible fungus risks your lawn could face if irrigated at night. Shoot for 6-10 am.
• Adjust fertilizer applications to avoid damage. In high stress periods, light fertilizer applications will keep your lawn healthy or assist in recovery.
• If the drought is severe enough, let it go dormant. In conditions when the heat is just too much for your grass to overcome, it will essentially shut down until cool, moist weather returns. During this condition, you should irrigate your lawn at least once per week.
• If you have a newly-planted lawn, don’t let it go dormant. Every rule has an exception. Allowing new turf to dry up and die can have crippling long term effects, as it has shallow roots and may not be able to recover from extreme stress. It is critical to keep up with irrigation and refrain from compacting the soil in order to keep these lawns alive and well.

When autumn comes, your lawn should begin to recover from heat stress. Keeping up with seasonal lawn care is an essential part of maintaining healthy grass and can produce a wonderful lawn if performed correctly.