Lawn Fungus Treatments: Types, Costs, and Effectiveness for a Healthy Lawn

Lawn fungus can quickly turn a lush green lawn into a patchy mess of wilted and discolored grass. These tiny organisms, known as fungi, enter the grass tissue, using it as a source of nutrients to grow and multiply. They can cause significant damage to the lawn, and in severe cases, even kill the grass. Understanding the types of lawn fungus treatments available, their costs, and their effectiveness is crucial to maintaining a healthy and vibrant lawn. In this comprehensive guide, we will explore various lawn fungus treatments, including their costs, types, and effectiveness, along with tips on prevention and lawn care practices. So let’s dive in!

What is Lawn Fungus?

Before we explore the various treatments, let’s first understand what lawn fungus is and how it affects your lawn. Lawn fungus refers to the presence of fungal organisms in the grass, which can lead to the development of various diseases. These fungi typically reside in the thatch layer, fallen leaves, and other organic matter in the lawn. They spread through spores and hyphae, especially in warm and humid weather conditions, causing damage to the turfgrass.

Several factors can make a lawn more susceptible to fungal infection. Dormancy plays a significant role, with different grass types being vulnerable at different times of the year. Cool-season grasses like Kentucky bluegrass and fescues are more susceptible during the summer when they enter dormancy, while warm-season turfs like Bermudagrass and Zoysia are at higher risk during the fall and early spring when transitioning in and out of dormancy.

Stress factors such as drought, high temperatures, scalping, under-fertilization, overwatering, soil compaction, and damage from pests and diseases can weaken the turfgrass, making it more susceptible to fungal infections.

Identifying Lawn Fungus

Identifying lawn fungus is crucial for effective treatment. By recognizing the signs and symptoms, you can take timely action to prevent further damage to your lawn. Here are some common signs of lawn fungus infestation:

  1. Straw-like or brown spots: Infected grass may develop straw-like or brown spots on the leaves. These spots may also appear in other colors like orange or pink.
  2. Withered or yellow leaves: Fungal diseases can cause the grass leaves to wither, bleach, or turn yellow.
  3. Rot on leaf sheaths, crowns, and roots: You may notice brown or black rot on the leaf sheaths, crowns, and roots of the grass plants.
  4. Cottony growth on plants and soil: Fungi often produce a dark or whitish, cottony growth on the affected grass plants and in the soil.
  5. Pea-like structures on grass leaves: Some fungal infections can result in the formation of small, rigid pea-like structures called sclerotia on the grass leaves.
  6. Irregular or circular patches: Infected areas of the lawn may exhibit irregular or circular patches with grass discoloration. These patches may have taller and greener grass or even mushrooms growing in them.
  7. Wilted or dead grass: In severe cases, the infected grass may appear wilted or completely dead in certain patches of the lawn.

Types of Fungicides

Fungicides are chemical or natural substances used to control and prevent fungal infections in lawns. They can be classified into two main types: contact and systemic fungicides.

Contact Fungicides

Contact fungicides form a protective layer on the surface of the grass, preventing fungi from entering the plant. These fungicides are not absorbed into the plant tissue and must be reapplied every seven to 14 days. While they are less durable and require repeated applications, contact fungicides are effective as a preventative measure or for treating small localized infestations.

Some common active ingredients found in contact fungicides include Captan, Citric acid, and Neem oil. Neem oil, in particular, is a natural fungicide that has shown good results against powdery mildew and brown patch disease. It can be mixed with water to create a DIY neem fungicide, with an application rate of 2.5 gallons per 1,000 square feet.

Systemic Fungicides

Systemic fungicides, also known as penetrants, are absorbed into the plant tissue, allowing them to target fungi inside the plant and halt the infection. They are most effective when applied within 24 to 72 hours after infection, as their effectiveness decreases once the fungi have heavily colonized the grass.

Systemic fungicides are generally longer-lasting compared to contact fungicides, with a single application lasting up to four weeks. This makes them easier to use and less costly in the long run. Some commonly used systemic fungicides for home lawns include Azoxystrobin, Propiconazole, Pyraclostrobin, Myclobutanil, and Thiophanate-methyl.

Natural Fungicides

Natural fungicides offer an eco-friendly alternative to chemical fungicides. While they may work slower than their chemical counterparts, they are safer to use and less damaging to the environment. Some effective natural fungicides include Neem oil, clove oil, and lemon juice (citric acid).

Neem oil, in particular, has been found to prevent spore germination and the penetration of leaf tissue. It can be applied as a DIY solution by mixing one ounce of neem oil with one gallon of water. The solution should be applied at a rate of 2.5 gallons per 1,000 square feet. Neem oil is readily available and costs between $1 to $1.50 per ounce or $2.50 to $3.75 to treat 1,000 square feet.

Biological Fungicides

Biological fungicides, also known as biofungicides, utilize beneficial microorganisms to protect the grass from pathogenic fungi. These microorganisms, such as Bacillus amyloliquefaciens, Bacillus subtilis, and Trichoderma species, act on multiple fronts to prevent fungal infections. They can also colonize the roots, form a protective barrier, consume excess nutrients in the soil, and release enzymes that denature the cell walls of fungal pathogens.

Biological fungicides are easy to use, affordable, and more durable than other options. They are also eco-friendly, and fungi do not develop resistance to them. Some well-known brands offering biological fungicides include Bonide, Southern AG, and Monterey.

Broad-Spectrum vs. Narrow-Spectrum Fungicides

Fungicides can also be classified as broad-spectrum or narrow-spectrum based on their target range. Broad-spectrum fungicides control multiple unrelated groups of fungi, making them a good choice when you are unsure about the specific pathogen infesting your lawn. They offer a higher chance of effectively targeting the fungi present in your lawn. Examples of broad-spectrum fungicides include azoxystrobin, which controls various diseases such as anthracnose, brown patch, leaf spot, fairy rings, necrotic ring spot, and pythium blight.

On the other hand, narrow-spectrum fungicides are designed to target specific groups or species of fungi. To achieve desired results with narrow-spectrum fungicides, it is essential to accurately identify the pathogen causing the infestation in your turf. Unlike broad-spectrum fungicides, narrow-spectrum fungicides do not harm beneficial fungi like Arbuscular mycorrhizal, which help in the growth of grass. Identifying the specific pathogen can be done through a grass sample test at a plant pathology lab near you or by consulting a lawn care professional or local Cooperative Extension Office expert.

Delivery Methods

Fungicides can be applied in liquid or granular form, depending on your preference and the specific product. Each method of delivery comes with its own set of advantages and considerations.

Liquid Fungicides

Liquid fungicides are applied using a sprayer. You can use a hose-end sprayer connected to a garden hose for small lawns or a backpack pump sprayer for larger areas. Liquid formulas are generally faster-acting, as they are more easily absorbed into the foliage and soil. They typically cost around $5.25 per 1,000 square feet.

When applying liquid fungicides, it is crucial to wear appropriate safety equipment such as safety glasses or goggles, a mask, gloves, long sleeves, and close-toed shoes. Ensure that children and pets are kept away from the treated area until the solution has dried.

Granular Fungicides

Granular fungicides are applied using a lawn spreader. They take longer to work compared to liquid fungicides, as they need time to dissolve and penetrate the soil. Granular products are typically priced around $7.75 per 1,000 square feet.

As with liquid fungicides, safety precautions should be taken while applying granular fungicides. Wear appropriate safety equipment and keep children and pets away from the treated area.

Explore Eco-Friendly Options at EcoLawn Florida: If you prefer eco-friendly alternatives, EcoLawn Florida offers natural and biological fungicides. Discover sustainable solutions to protect your lawn without harming the environment.

Applying Lawn Fungus Treatments

While some homeowners prefer to leave fungal treatments to professionals, applying them yourself can be simple and cost-effective if done correctly. Here are four steps to follow when applying lawn fungus treatments to your lawn:

1. Determine if Fungicide is Needed

Before applying a fungicide, it is essential to determine if your lawn truly requires treatment. Some symptoms of fungal diseases can be similar to damage caused by other factors, such as improper watering, fertilizing, or mowing, as well as pest infestations or extreme temperatures. Conduct a thorough inspection of your lawn, checking for signs of fungal disease and considering other potential causes of damage.

2. Select the Right Fungicide

Choosing the right fungicide is crucial for effective treatment. Different fungal diseases require different types of fungicides, and not all diseases require chemical control. Some diseases can be managed through cultural practices such as proper lawn maintenance.

Reference the chart below to help identify the specific lawn fungus affecting your turf:
Lawn Fungal DiseaseMain Signs and Symptoms
Dollar SpotSmall, circular, dollar-sized yellow, straw-colored, or light brown spots extending up to five inches wide
Red ThreadReddish or pinkish patches up to two feet wide
Brown PatchSmall, irregular brown patches with sunken centers up to a few feet wide
Large PatchSmall, irregular areas up to 12 inches wide with tan-orange grass
Yellow PatchCircular yellow to light-brown patches five inches to a few feet wide
Pythium BlightSmall circles of withering, blackened, or reddish-brown grass two to six inches wide following water patterns
Fairy RingsCircular or semi-circular bands of taller, greener grass, dry, straw-colored to light brown turf, or mushrooms
Gray Leaf SpotIrregular blighted patches with bleached, twisted leaves and small, water-soaked lesions, sometimes covered in grayish spores
Powdery MildewLight green whitish areas that look like chalk powder
Spring Dead SpotCircular spots of bleached-out, dead grass, six to 12 inches wide; can merge into larger patches
Summer PatchYellow to tan circular areas of dead grass up to one foot wide
RustShifts from golden yellow to orange rust; irregular patches with orange powder
Leaf SpotIrregular areas of off-color turf; grass stems, sheaths, and blades possess elongated or circular light brown spots
Melting OutPatches of yellow to blackish-brown wilted or dead grass; dark brown rot on roots and crowns
Take-all Root RotChlorotic, yellow to light green patches that eventually turn brown, thin out, and become bare areas
Leaf BlightIrregular patches with blighted, straw-colored, or brown grass; appear overnight
Different turfgrass species are susceptible to specific lawn fungal diseases. Here are some commonly affected grass types:
Lawn Fungal DiseaseSusceptible Grasses
Dollar SpotFine fescue, perennial ryegrass, bentgrass, centipedegrass, Kentucky bluegrass, tall fescue, Bermudagrass, and Zoysiagrass
Brown PatchRyegrass, tall fescue, creeping bentgrass, Kentucky bluegrass, and fine fescue
Red ThreadFine fescue, perennial ryegrass, bentgrass, and Kentucky bluegrass
Large PatchZoysiagrass, Centipedegrass, St. Augustine, and Bermudagrass
Pythium BlightPerennial ryegrass, creeping bentgrass, fine fescues, and bluegrasses
Yellow PatchCreeping bentgrass, Kentucky bluegrass, perennial ryegrass, Bermudagrass, and Zoysiagrass
Fairy RingsAll lawn grasses
Powdery Mildew Kentucky bluegrass and fescues
Gray Leaf SpotSt. Augustinegrass, perennial ryegrass, centipedegrass, tall fescue, and Bermudagrass
Spring Dead SpotBermudagrass, seashore paspalum, and Zoysiagrass
Summer PatchKentucky bluegrass, fescues, bentgrass, and annual bluegrass
RustKentucky bluegrass and perennial ryegrass
Leaf SpotKentucky bluegrass, perennial ryegrass, and tall fescue
Melting OutKentucky bluegrass, perennial ryegrass, and tall fescue
Take-all Root RotAll warm-season turfgrasses
Leaf BlightAnnual bluegrass, creeping bentgrass, perennial ryegrass, tall fescue, Kentucky bluegrass, and fine fescue
Gray Snow MoldAll cool-season turfgrasses
Pink Snow MoldAll cool-season turfgrasses
AnthracnoseAnnual bluegrass, creeping bentgrass, Kentucky bluegrass, fine fescues, perennial ryegrass, and Bermudagrass

Once you have identified the specific fungal disease affecting your lawn and the susceptible grass species, you can choose the appropriate fungicide for treatment.

3. Follow Safety Precautions

Whether you are using chemical or natural fungicides, it is essential to prioritize safety during application. Wear safety glasses or goggles, a mask, gloves, long sleeves, and close-toed shoes to protect yourself from any potential hazards. Keep children and pets away from the treated area until the solution has dried to prevent accidental exposure.

4. Apply Fungicide

To ensure successful fungicide application, consider the following factors:

Volume: Generally, fungicide applications require two to four gallons of solution per 1,000 square feet of lawn.

Spray nozzle type: Hollow-cone nozzles that produce medium-fine droplets are recommended for even coverage.

Spray pressure: Maintain a spray pressure of 40 to 60 pounds per square inch for optimal coverage and canopy penetration.

Timing: Apply preventive treatments before infestation, typically after heavy rain or during high-humidity seasons. Consider past weather patterns and your local climate to determine the best window for preventative applications.

Repetition: Reapply the fungicide at intervals of seven to 14 days until the infestation is completely eliminated. Adhere to the manufacturer’s guidelines concerning application rates and frequency.

It’s important to note that successful fungal treatments are just one aspect of a comprehensive pest management strategy for your lawn.

Lawn Care Practices for Fungus Control

While treating your lawn for fungal infections is crucial, implementing proper lawn care practices can help prevent future infestations and promote overall lawn health. Here are some key practices to incorporate into your lawn care routine:

Work on healthy areas first

When mowing, aerating, fertilizing, or performing any other lawn care activities, prioritize working on healthy areas first to prevent the spread of fungal spores.

Clean lawn care equipment

After each use, clean your lawn care equipment and ensure that mower blades are sharpened annually. This helps prevent the spread of fungal spores.

Remove grass clippings

Regularly remove grass clippings from your lawn, as they can harbor fungal spores and create an environment conducive to fungal growth.

Mow your lawn taller

Adjust your mower height to a higher setting, as longer grass blades provide shade and reduce moisture on the soil surface, making it less favorable for fungal growth.

Avoid mowing wet grass

Never mow your lawn when the grass is wet, as this can spread fungal spores and increase the risk of fungal infections.

Aerate and dethatch your lawn

Regularly aerate and dethatch your lawn to improve soil drainage and reduce compaction, which can contribute to fungal infections.

Watering practices

Avoid watering your lawn in the evening, as this can create prolonged moisture on the grass blades. Instead, water deeply and less frequently to promote deep root growth and reduce surface moisture.

Remove morning dew

If possible, remove the morning dew from your lawn using a leaf blower or a lightweight rake. This helps minimize the moisture on the grass, which can contribute to fungal growth.

Trim trees and shrubs

Trim trees and shrubs near your lawn to improve air circulation and sun exposure. Adequate air circulation and sunlight can help prevent fungal infections.

Regular pest and grub control

Implement regular pest and grub control measures to prevent damage to your lawn, as weakened grass is more susceptible to fungal infections.

Lawn Recovery After Fungal Disease

Recovering your lawn after a fungal disease takes time and patience. Here are some steps you can take to aid the recovery process:

  1. Continue mowing: Regular mowing gradually removes damaged grass blades and promotes new growth. Ensure that your mower blades are sharp to prevent further stress on the grass.
  2. Apply grass paint: If you have off-color patches in your lawn and need a quick fix for aesthetic purposes, consider applying grass paint. Grass paint can temporarily restore the green appearance of your lawn.
  3. Install sod: If the fungal disease has caused bare patches in your lawn, remove the dead grass and replace it with new sod. Ensure that the soil is properly prepared before installing the sod for optimal growth.
  4. Overseed: Overseeding can help fill in thinning areas of your lawn and prevent weed growth. Also, choose resilient grass seed varieties that are suitable for your climate and grass type.


Effectively treating and preventing lawn fungus is crucial for maintaining a healthy and vibrant lawn. You can make informed decisions about protecting your lawn by understanding the different types of fungicides available, their costs, and their effectiveness. Remember to identify the signs of lawn fungus, choose the right fungicide for the specific disease, and follow proper application techniques. Additionally, incorporate good lawn care practices to minimize the risk of fungal infections in the future. With the right knowledge and proactive approach, you can keep your lawn fungus-free and thriving throughout the seasons.

Ready to revive your lawn and keep it fungus-free? Visit ECO Lawn Florida for expert lawn care solutions. Transform your patchy mess into a lush, vibrant haven with our proven lawn fungus treatments and eco-friendly practices. Your dream lawn is just a click away!