Maintaining cool-season turf health in warmer weather requires diligence and planning. Learn a three-fold strategy that’ll keep your client’s turf disease-free.

It’s go-time for lawn and landscape managers as spring signals the start of the active growing season for cool-season turf. To ensure hearty turf conditions that hold disease pathogens short of the goal line, managers need to organize a well-rounded game plan. In this article, we share the keys to developing a winning strategy:

lawnFielding a strong defense: Seven practices to strengthen your lawn clients’ environment

The first step is to understand the players. Disease pathogens require a vulnerable plant host and assisting environmental conditions to mount an attack. A disciplined defense—one that keeps these three vital players from coming together—is the best way for defeating disease pressure across the season.

Be disciplined in the following lawn care management practices to ensure your conditions favor strong turf and resist the spread of disease. Maximizing all cultural advantages to allow exceptional turfgrass growth is key to maintaining a healthy disease-free lawn.

1. Plan ahead.

It’s important to be proactive. Implement targeted preventive fungicide applications based upon your experience at the site and be sure to scout and closely follow the weather conditions to set your application schedule. The combination makes for a strong foundation of a disease-free lawn.

A well-timed preventive fungicide application for diseases such as fairy ring and summer patch will lessen or eliminate problems when the pathogen has yet to damage the turf or is in an early and vulnerable stage.

2. Proper mowing.Nufarm mowing heights

Recommend that your clients maintain sharp mower blades to reduce plant damage and mow regularly to attain the proper height for your turfgrass type. Encourage them to reduce grass height by no more than one-third in a single cutting.

Mowing too short disrupts nutrients and weakens plants; meanwhile, leaving grass too tall inhibits sunlight and provides an excellent environment for fungal diseases to thrive.

3. Wise watering.

Poor irrigation practices, whether over- or under-watering, invite disease activity. Be vigilant in suggesting your clients address overly wet or dry areas, which can strongly weaken turf and assist disease.

4. Focused fertilization.

Nutrient-depleted turfgrass is more prone to disease. Over-fertilization can run the same risk, raising the plant’s susceptibility to various diseases. Lawn and landscape managers should soil test to gauge nutrient needs. Depending on the soil sample results for each site, apply slow-release fertilizer in the spring, generally leaning toward lower application rates.

5. Canopy health.

Compacted soil limits root growth, leaving turf susceptible to disease. Cultivation with coring or aeration reduces compaction and is best done when grass is in high growth, before temperatures reach stress levels. Promptly reintegrate core segments using drag equipment. De-thatch to further support root health.

Nufarm6. Strategic seeding.

Cool-season grasses are often prone to summer disease. Select a turfgrass type well suited to your conditions. If your turfgrass type isn’t optimal, consider introducing or seeding a new variety that demonstrates a higher level of disease resistance while also producing more consistent desirable qualities such as density, uniformity and color.

7. Accurate identification.

Frequently inspect your turf for early signs of disease. Once disease is present, it’s important to identify the causal pathogen so you can determine the best course of action. Lawn and landscape professionals can consult reference materials, ask an expert or send a sample for testing to determine the pathogen. Once identified on site, act quickly to apply an effective curative fungicide treatment according to label directions.

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Disease highlights: Five cool-season diseases to watch

Not all diseases are the same, and they can’t all be treated the same. It’s important to know what to watch for so you can treat it early. Here are five diseases that can threaten your clients’ cool-season turfgrass this season.

1. Brown patch

Brown patch appears as somewhat circular patches of brown, tan or yellow blighted grass from five inches to several feet wide. A dark edge known as smoke ring may surround patches in wet or humid conditions (often in morning), signifying active disease development.
Chazz Hesselein, Alabama Cooperative Extension System,

Photo: Chazz Hesselein, Alabama Cooperative Extension System,

2. Dollar spot

Symptoms of dollar spot include sunken circular patches up to several inches in diameter. Patches turn a brown to straw color and may eventually combine to form irregular shapes. Leaves can present yellow-green lesions with reddish-brown edges. Affected roots darken.
Mary Ann Hansen, Virginia Polytechnic Institute and State University,

Photo: Mary Ann Hansen, Virginia Polytechnic Institute and State University,

3. Melting out & leaf spot

Melting out is active in cool, wet spring; leaf spot in summer. Both appear as small reddish-brown or dark purple spots on leaves and stems that rapidly spread. Older spots become “eyespots” (with buff-colored centers and dark margins). Leaves eventually form patches of dead, thin, yellow grass.
William M. Brown Jr.,

Photo: William M. Brown Jr.,

4. Summer patch

Symptoms initially resemble drought stress, presenting as small 1 in. to 3 in. patches of pale grass with leaves turning gray, brown or straw-colored. Patches may expand and leaves may develop white streaks in response to heat and root damage.
Mary Ann Hansen, Virginia Polytechnic Institute and State University,

Photo: Mary Ann Hansen, Virginia Polytechnic Institute and State University,

5. Fairy ring

Fairy ring appears as darkened arcs, rings or patches that are initially less than 12 in. in diameter, but expand in size each year. The diseased turf can support fruiting bodies such as mushrooms and puffballs. Roots show orange discoloration and may have a strong mushroom odor.
Lester E. Dickens,

Photo: Lester E. Dickens,

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Build a strong offense: Two fungicides to help you win

When necessary, fungicide treatments with products such as Nufarm Tourney® or 3336® F provide preventive and curative performance to combat a wide range of challenging turfgrass diseases. Always read and follow label directions.

Tourney fungicideTourney Fungicide is one of the most active fungicides on the market, controlling many difficult to control lawn diseases for up to 28 days while improving turf quality.

3336 F fungicide3336 F is a broad-spectrum fungicide with a systemic mode of action that is particularly effective on a wide range of diseases.

Visit to learn more.

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3336® is a registered trademark of Nufarm Americas, Inc. Tourney® is a registered trademark of Valent U.S.A. LLC.

This page was produced by North Coast Media’s content marketing staff in collaboration with Nufarm. NCM Content Marketing connects marketers to audiences and delivers industry trends, business tips and product information. The Landscape Management editorial staff did not create this content.