Turf Heat Stress and Fungus

Turf Heat Stress and Fungus


As we all know, our region experiences many extremes in terms of weather conditions. During the winter months we see freezing temps/snow and during the summer our area can go through very hot & dry periods. The hot summer months can cause significant damage to the lawn and it's important to appropriately diagnose any turf issues that are common as a result from the heat.
Below we'll break down the two most common summer issues we see with our turf: Heat Stress and Fungus

Heat Stress

Most turf in our area is considered to be "Cool Season Grass" and it gets that moniker from the fact that it does so well during the cooler seasons. The spring and fall bring out that dark green healthy turf look but during the summer months the grass doesn't fair so well. We try to counter the hot dry months with a solid fertilizer program (N) and increased watering but it's still very hard to keep some areas of the lawn healthy even with these measures.
One of the most common heat related turf issues we see during the summer is "Turf Heat Stress". This is when the grass essentially shuts down due to the increased heat and lack of increased water to compensate. The first stage of heat stress will bring slowed growth but you won't necessarily see the grass change color yet. Stage two can bring a slightly purple look, almost now growth, and the grass will be very dry when touching. With stage three the grass turns light brown and looks like straw/hay when holding in your hand.

The fact of the mater is that it's tough to avoid some patches of heat stress from developing from June - August in our area since it can get so hot and dry. The nitrogen included with our fertilizer programs helps reduce chances of heat stress and also increased watering can reduce the possibility of the lawn drying out. In our experience the overall best chance at avoiding heat stress is to have a professional sprinkler system installed and then to have a water management program developed by someone who is trained in Evapotranspiration Water Scheduling. This type of watering plan sets a "base" schedule for your property per your lawns soil type/conditions, evapotranspiration rates, sprinkler hardware on site, and local historical weather averages. Once your base schedule is created you'll then increase/decrease a set % amount each month to compensate for the seasonal changes.

If it's too late and your lawn has already been damaged due to heat stress you'll want to increase your watering schedule and also be setup with our fall turf repair services. These include fall aeration & seeding, lawn application #5, and compost top-dressing service. All three of these treatment options are designed to repair the damage caused by the hot summer months and prepare the lawn for the extreme winter months ahead. Increasing your watering schedule combined with our fall turf services will give the lawn the boost it needs to get that dark green healthy look during the cooler months ahead.


Commonly mistaken as heat stress, fungal disease is also a common turf issue that we experience in our region. If the lawn is looking lush/green but getting random brown patches within those green areas, it could be fungus ("brown patch" is the most common fungal disease). While it can look the same as heat stress, brown patch looks different up close because the blades themselves have brown spots on them and the area closest to the thatch layer will be warm and damp.

Most of the brown turf areas we see with the lawns we service are heat stress related but we've also had to treat some with a fungicide to stop the spread of brown patch. When we diagnose a lawn to have a fungus problem we recommend 1-3 treatments with a fungicide and it will treat and usually reverse the issue very quickly. These treatments are outside of our regular program and pricing starts at $149 per visit.

Outside Resources

Below is a great video that we found on YouTube from Picture Perfect Lawn Maintenance (Dinwiddie, Virginia 23803) explaining the difference between Turf Heat Stress and Fungus. We highly recommend watching the video and if you know anyone in their area please recommend them as a lawn care provider!

    • Related Articles

    • How Often Should You Cut Your Grass?

      How Often Should You Cut Your Grass? One of the questions we hear the most is, "How often should I be cutting my lawn?".  Well, it depends. During the spring months we're usually mowing properties every week or so.  That's because it's a fast growing ...
    • Controlling Grubs in Your Lawn

      Controlling Grubs in Your Lawn     Keep on the lookout for Grubs! If your lawn starts to turn brown and wilt in certain areas, you may have grubs. Grubs are small white larvae of beetles that feed off of grass roots, causing your lawn to brown and ...
    • Dog Urine and Lawn Burn

      Avoiding Lawn Burn from Dog Urine Why does it burn the lawn? Dog waste is very high in Nitrogen.  This is usually because diets high in protein produce waste that's high in Nitrogen, and too much can burn the grass.  This can especially be a problem ...
    • At What Height Should You Mow Your Grass?

      At What Height Should You Mow Your Grass? The Higher The Better! There are many different reasons why most experts now recommend a longer turf grass.  Here's just a few: Promotes longer root growth Provides shade to soil beneath, which reduces weed ...
    • Lawn Fertilizer FAQs

      Can you explain the signup process? First, browse the shop, add to cart, and then checkout via your preferred payment option. Once your order is placed our office is alerted and will begin processing your order. You'll receive a couple of onboarding ...