What do you do when your beautiful lawn looks like it’s been taken over by a circular superbug? Brown patch will not only kill your curb appeal but will also affect the overall health of your grass. To help you get started, discover how to get rid of brown patch fungus and ways to prevent it from appearing in your yard again.
What is brown patch disease?
Brown patch is a fungal disease that attacks cool-season and warm-season lawns. It thrives during humid weather and warm months (late spring through late summer). Caused by a strain of Rhizoctonia solani, brown patch will lay waste to your lawn and cause dead grass under conditions like:
- Poor drainage
- Soil compaction
- Thick thatch
- Shaded areas
- Acidic soil pH
- Too much nitrogen fertilizer
- Low phosphorus and potassium
- High humidity
- Daytime temperatures above 90 degrees Fahrenheit and nighttime temperatures above 70 degrees Fahrenheit
How to identify brown patch
Like most lawn fungi, brown patch is tricky to identify. In some cases, it is confused with large patch, another lawn disease affecting warm-season grasses like Bermudagrass, Zoysiagrass, and St. Augustinegrass.
Despite the confusion, brown patch displays some recognizable symptoms:
- Circular tan, brown, yellow, or orange patches on the lawn. They can be as small as a few inches or as large as a few feet wide.
- If your lawn is cut above 1 inch, you may see mycelium (looks like a spiderweb) on the leaves when wet (with dew, for example).
- Tan lesions on the grass blades, with a brown ring around the edges.
- A “smoke ring” (black ring) around the circular patches. This is especially the case with low-cut grass.
Pro tip: If you want to be 100% sure of your diagnosis, contact your local Cooperative Extension Office. An expert can help you ID the disease via a grass sample or photo.
How to get rid of brown patch
Once the brown spots overtake your lawn, you need to eliminate them pronto. Although turfgrass fungus can be notoriously difficult to get rid of, it’s certainly not impossible. Here are a few tried and true ways to help your lawn recover from this unsightly disease:
Organic treatments
If you’re looking for a natural product to treat your lawn, look for products with the active ingredient Bacillus amyloliquefaciens strain D747. Most of these products will be OMRI-certified, meaning they can be used in organic production.
Other organic treatment options at your disposal include:
- A spray mixture of one gallon of water, one teaspoon of vegetable oil, and one tablespoon of baking soda.
- Neem oil, which you can purchase at any local garden center. Mix it with the amount of water specified on the label and spray all brown patch areas.
- Horticultural cornmeal is an antifungal solution to your brown patch problem. We recommend about 2 pounds of cornmeal for 100 square feet of affected lawn. Spread it by hand or use a spreader for even distribution. Alternatively, try the cornmeal tea solution by mixing 5 gallons of water with about one cup of cornmeal and let it sit for 30 minutes to an hour. Spray it as needed over your lawn.
Pro tip: Spray target areas as often as needed until the brown patch goes away.
Chemical treatments
There are several commercially available fungicide treatments for brown patch, either in liquid or granular form. Read the label carefully to make sure the product controls brown patch and works for your grass type. Also, pay close attention to the temperatures needed to apply your chosen fungicide, as some products are useless in extremely high temperatures.
Lawn fungicides to treat brown patch include:
- BioAdvanced Fungus Control (with Propiconazole)
- Pyraclostrobin with Triticonazole
- Fluoxastrobin
Pro tip: Applying azoxystrobin or fluoxastrobin on their own may lead to brown patch fungus resistance. Choose a product with at least two active ingredients for optimal effectiveness.
If you notice brown patch fungus in your lawn during the summer, you can apply fungicides right away, but remember that this approach may not produce results quickly. Cool-season grasses, like Kentucky bluegrass, grow more slowly in the summer, so treatments should be applied in the spring or early summer at the latest. Warm-season grass can be treated in the spring or fall for ideal disease control.
Step-by-step
- Begin by dethatching affected areas. Follow up with core or spike aeration to improve air movement and allow the fungicide to penetrate the soil.
- As soon as nighttime temperatures rise above 60 degrees Fahrenheit, start your first round of fungicide applications, keeping to problem areas rather than targeting your entire lawn. Alternatively, you can contact a professional lawn care company to handle the process for you.
- Once the problem is gone, reseed with your grass of choice to bring your lawn back to life. You may have to repeat this process several times to see the desired results.
How to prevent brown patch
You can’t eliminate the fungi that live in your soil, but you can keep your lawn healthy to prevent unnecessary stress during transitional seasons. Check out this list of common lawn problems and corresponding DIY solutions you can try at home:
| Problem | DIY Solution |
| Soil pH is below 6.0 | Follow your soil test’s recommendations for lime applications to raise the soil pH. |
| Poor soil airflow | If you have cool-season grass, try aeration in the fall. |
| Your lawn stays wet for a long time | Change your watering schedule. Water in the early morning between 6 a.m. to 10 a.m. |
| Not enough phosphorus or potassium | Follow your soil test’s recommendations to correct the problem. |
| You only have one cultivar or species planted in the lawn | Overseed your lawn with a different cultivar or a cool-season mix that includes different grass species. |
| Too much shade | Consider trimming back trees or planting a grass alternative in the area. |
| Thick thatch–over ½ inch or more | Rent a dethatching machine and go to town. |
| How to avoid spreading the disease while mowing | Mow the lawn to the correct height and save the affected areas for last. Remove grass clippings. Never mow a wet lawn. Clean your lawn care tools after each use. |
FAQ about how to get rid of brown patch
What’s a quick solution to those brown spots on my lawn?
If you want to make those brown spots go away pronto, paint your lawn. Yes, it’s a legitimate practice, and it’s quite popular in drought-stricken areas in the West. Think of it this way: It’s like makeup for your lawn. Grass paint helps your grass look good even when it’s fungus- or drought-stricken.
Are some grass types more susceptible to brown patch than others?
Although brown patch can infect both cool-season and warm-season grasses, the cool-season varieties are more often affected by this disease. If you have Kentucky bluegrass, bentgrass, tall fescue, or perennial ryegrass, keep a close eye on your lawn.
Can I bring my lawn back to complete health after brown patch?
It may take some time, but your lawn will recover if you apply the correct treatment and practice responsible lawn care. If unsure, a professional lawn care company can restore your lawn’s health and prevent future diseases.
Professional help at your fingertips
Dealing with brown patch or other lawn problems is no easy task. If you’d rather have a professional manage this fungal disease, let Lawn Love connect you with a local lawn care professional. They have the experience and expertise to deal with common lawn issues and bring your turfgrass back to a healthy lawn.
Main Photo Credit: Mr Thinktank | Flickr | CC BY 2.0
