How to Deal with Grass Fungal Diseases in Your Lawn

Irregular patches of fungal disease in centipede grass lawn.
Irregular patches of fungal disease in centipede grass lawn.

Lawn fungal diseases take on a variety of forms – from dead-looking brown patches to highly visible spots, threads, rings, or slimes. And once they strike your yard, grass fungal diseases can be difficult to treat.

Fortunately, the right lawn care practices can go a long way toward prevention and treatment; and in severe cases, a fungicide can help eradicate the spores to keep it from spreading. Here are some tips for preventing and treating fungal diseases in your lawn.

Mowing grass in yard with lawn mower
Mowing your grass too low can encourage fungal disease.

Causes of Lawn Fungal Disease

Your lawn is naturally full of fungi and spores, some harmless and some problematic, but the right (or wrong) conditions can cause grass fungus to erupt into a harmful disease. The most common causes of a lawn fungal disease are:

  • Drought
  • Improper mowing (especially mowing too low)
  • Compacted soil
  • Overwatering
  • Too much fertilizer (or using the wrong kind)
  • Wrong grass type for your yard
  • Weather conditions (particularly temperature and humidity)

How To Identify Lawn Fungal Diseases

Signs that your lawn may have a fungal disease include:

Brown patch of dead grass in lawn
Brown patch of dead grass in lawn.
  • White, yellow, or brown patches or rings that grow in diameter.
  • Thin patches of frayed, distorted, or discolored grass blades.
  • Gray, black, red, orange, or purple spots on blades or stems.
  • Gray, black, or pink powdery or threadlike coatings on and around grass blades.
  • Areas of darkened, wet-looking, slimy, or greasy-looking grass.

Common Lawn Fungal Diseases

There are quite a few fungal diseases that can impact lawns, but they’re usually pretty specialized, targeting specific lawn types, at certain times of year, under certain conditions. For example:

  • Brown patch strikes during hot, humid weather.
  • Fusarium blight prefers hot, drought conditions.
  • Dollar spot tends to spring up when nights are cool and dew is heavy.

Before treating your lawn, it’s important to identify not only whether your lawn indeed has a fungal disease, but to identify the fungus itself. All fungicides aren’t the same, and some diseases can be easily treated by making changes in your lawn care.

Knowing your grass type and recent weather conditions can make it easier to narrow down, but you may need help in figuring out exactly what’s going on. Your local cooperative extension center is your best resource for determining which diseases are most common in your area, or you can take a small baggie of the infected grass to your local garden center for help.

Using a fertilizer spreader to apply antifungal treatment to lawn
Applying an antifungal treatment may be necessary to treat severe cases.

How To Prevent and Treat Lawn Fungal Diseases

A simple change in your lawn care practices may be enough to prevent or eradicate lawn fungal disease. At other times nature may deliver a soggy spring or summer heat wave that just can’t be helped. Stressed or unhealthy lawns are much more likely to develop disease; so the better you care for your lawn, the better the grass will be able to handle the natural conditions in your area.

Follow these steps to help take control of fungal diseases in your lawn:

  • Soil Test: Conducting a soil test can not only identify nutrient deficiencies that lead to stressed lawns and disease but sometimes can be used to diagnose the disease itself. Check with your local cooperative extension office for more information.
  • Aerate: Loosen soil by aerating your lawn every year or two.
  • Top-Dress: Apply and rake in a layer of rich, organic top-dressing to improve the soil, increase drainage, and help combat disease.
  • Dethatch: Remove thick buildups of thatch in your lawn to allow the soil to breathe.
  • Sprinkler watering lawn.
    Improper watering can lead to lawn fungus.
  • Grass Type: Rather than fighting nature to have an exotic lawn, choose a grass type that’s suited for your climate, soil, and light conditions. Well chosen lawns are stronger and able to fight off the normal fungal spores native to the area.
  • Go Organic: Synthetic fertilizers, pesticides, and other lawn chemicals can upset your lawn’s ecosystem – allowing disease organisms to grow unchecked. Using organic materials helps keep your lawn in balance.
  • Fertilizing: Both over and under fertilizing can promote some fungal diseases. Choose organic, slow-release fertilizers for your lawn, and apply them exactly as instructed. Avoid excess nitrogen, which creates a fast green lawn with very poor defenses.
  • Watering: Water early in the morning, to allow the grass blades to dry during the day. Give your lawn one inch of water per week, and use a rain gauge to keep track. Water deeply, but less frequently, to encourage stronger roots and to allow the water to absorb properly.
  • Mowing: Follow good mowing practices, including keeping the mower blades sharp and mowing your lawn to the correct height. Scalped lawns are much more vulnerable to fungal disease. If your lawn has diseased patches, be sure to wash and disinfect the underside of your mower after each use.
  • F-Stop Antifungal lawn treatment
    Antifungal grass treatment for lawn.
  • Air Circulation: Many lawn fungi develop under moist, still conditions. Thin out trees and shrubs to allow air to circulate all over your lawn, and plant shade-tolerant grasses under trees.
  • Snow: Avoid walking on or compacting snow in your yard during the winter, since heavy snow layers can breed snow molds that emerge in spring.
  • Go Natural: If certain areas of your lawn are prone to fungal disease due to conditions you can’t change, consider naturalizing the area with groundcovers or flower beds that will be better suited to those conditions.
  • Organic Treatment: Applying organic treatments – such as neem oil, compost tea, or a weak baking soda solution – can help with small patches of fungus.
  • Fungicides: If all else fails, look for a fungicide (preferably organic) that’s rated specifically for your lawn disease. Fungicides won’t help your grass regrow, but they’ll get the fungal spores in check so that your improved lawn care practices can take effect.

Further Information

59 COMMENTS

  1. seems to provide nothing about revitalizing a lawn the year after after the fungus has occurred, eg there was fungus here last year, but how do we deal with the results this year…re seed? refertlize etc as well as the mowing tips you provide.

  2. I was wondering can a fungus also be transmitted from your Gardner blades on his lawn mower From one lawn to another Any other disease be spread this way and how would you prevent this. We had new sod beautiful after about 5 months we had a fungus he has been treating it and it only seems to be getting worse. About 60% of our lawn looks gone? How do we know when the fungus is gone and we can re-seed?

    Thank you. From your article it looks like I do need to bring by grass/soil up for testing.

    Peggy

  3. What is the best prodcut for treating fungus in the yard. The grass I have 31 Fescue. I reseeded 2 years ago. My original grass was Falcon Fescue and Southern Choice. Cool season grasses. I need a good product to apply. Please advise – do I need a commercial grade or can find something at local Home Depot / Lowes?
    Thanks,

  4. I have a well known lawn service and they say you never get rid of brown patch or fungus you can only try and control it with their chemicals. Honestly I have it every year when the hot weather hits and the lawn looks awful. Next year I am not paying these people. I want a good answer on how to GET RID of fungus. I will do whatever it takes except move. I tried fungus control from Home Depot..didn’t work. There must be something out there that will get rid of it and not just control it.

  5. My lawn has large sections that are just barren and these large purple mushrooms that emit this dust red powdery substance comes off of them have tried turning the lawn and reseeding nOTHING Works

  6. After complaining to my lawn service for the past three or four years they finally decided to test the soil for a fungus. They applied fungicide on Bermuda grass 11/10.
    Is this the correct time of the year for this treatment?

  7. There is no cure. All you can do is treat it or apply fungicide prior to the time of year when it usually begins. Once you have it (brown patch) you have it forever Some years conditions will not be favorable so the lawn will remain healthy. As for cleaning the mower, some lawn maintenance companies say to use bleach(you can never reach every crevice and if you try this, don’t forget the tires) but the best medicine is to avoid mowing the areas when the fungus is active. The outside borders will be bright yellow and if you pull on the grass blades they will come out readily. Brown patch doesn’t usually kill your lawn (at least not St. Augustine-like grass with underground runners), it is just unsightly. Once the temp gets below 60 degrees, you can rake out the dead grass.

  8. Just laid sir Walter buffalo 5 weeks ago due to the unevenness off the grass I top dressed it with white washed sand. Some spots up to 40mm now I know to thick. Iam having green algae spits coming through the sand how do I rectify

  9. I’m in Michigan, and our snow is gone as of yesterday. I thought there was still a little left all over my front yard but I looked at it today, being it was 60 degrees and still white all over. Is it a fungus? Will this go away? I’ve never had this before and I don’t know what to do. I plan on raking the yard likely just to clean it up some, but should I be putting something on this or wait and see what happens? Thank you.

  10. The glass blades are red/brownish… I have a nice lawn not too many weeds…but after cutting and a close look at the grown, the grass blades are not all green…. Someone once told me I had ‘red grass’. What is the issue and how can I get a full green lawn…. I use scott products and fertilize regularly…….thanks…

  11. I completely sodded my front yard with St Augustine grass last November and this spring I applied Scotts Starter fertilized and the lawn grew beautifully until early June when I noticed a burned out section of lawn about 4 sq. ft. I thought it may be caused by fertilized, but by the end of June I noticed a few new patches and the original grew to about 7 sq. ft. I applied Scotts Fungus control and the bad patches stopped spreading but the lawn is a lighter green in the areas I treated. Since you can not purchase seed for St Augustine I have to remove the bad patches and re-sod ?
    Or do you have other suggestions ?

    Ralph

  12. Threads of white, scaley botches have appeared on my lawn, overnite. There are about twenty of them, in a 200 sq. ft. area. My lawn is about 15,000 sq ft. How do I stop & eliminate this disease?

  13. What if I’ve been walking around in the orange fungus, turning my toes orange. How do I get rid of all of that besides just washing my feet?

  14. My grass keeper told me that I have “Cominga”or Colinga don’t know which. He says the only way to get rid of it is to dig out the affected area and resod. If what he says is true, is there a cure? It seems to be spreading very rapidly.
    Thank You

  15. my lawn care guy came today for an application and I showed him on the side of my yard a completely dead grass area. He said it was dung aside. In the spring it was beautiful grass. I thought maybe my sprinklers weren’t hitting the area. Anyway before he left, he said he sprayed it. Not long after he left I went out to that area and it was bone dry! I called him and he told me the chemical dries very fast! I really don’t believe he put anything down!
    Please what is your thought?
    Kathy

  16. My grass has fungus like I can pull some of my grass easily. It look like its not in the soil, its on the top of soil. How can I treat it?
    Thanks

  17. What do you do to get rid of fungus in Northern Calif. And we have a lot to Dallas grass weed. It has been a drought year.

  18. I have some patches of fungus which are coloured green, mostly on the lawn edges. There are other areas on the lawn edges where there doesn’t appear to be any fungus and the lawn is receding more and more each year, so that only a few tufts of grass appear, but mostly there is just dirt showing. I try very hard to maintain my lawn by fertilising it, have it cored, use beetle killer on occasions and put gypsum on it a couple of times a year to break down the clay soil. I’m at a loss as to what I can do. Please can you help?

  19. I have a fungus, it is brown spots. Scouts yard company has treated the yard twice now for it. Is it OK for me to treat it with with other scouts fungus treatment? Or should T wait for results. they treat it every month.

  20. I have lawn that has a fungus gowth. It is black with white edges the black is shaped like a leaf the size is about 25 millimetres. the area of the infestation is roughly a square metre but there are other small areas appearing obviously transmitted by by mower. Any answers- appreciated

  21. How to prevent fungus diseases – is there any preventive chemicals available? Please someone give me some advise thank you.

  22. My soil tested positive for fungi years ago, but I cannot remember the name of the infection. When treating with fungicide the bald patch improves temporarily but the fungicide is expensive and I’d like to plant a ground cover impervious to fungus. The soil is sandy and in complete sun. I live near the Gulf of Mexico. Can you suggest a ground cover? Thank you

  23. I live in Connecticut. I have the darkest green and thickest lawn in town. My secret is very simple. Baking soda and Epsom salts. I use an old miracle grow bottle attached to the garden hose. First fill the bottle with baking soda and add water until bubbles stop. Attach to hose and start spraying. You will need to flip the bottle upside down and shake it to maintain mixture. You will notice white grasses turning yellow then orange. This is enough in that area. Once the whole lawn is done then fill the bottle with Epsom salts using the same shake and flip procedure. You want wet the lawn well with this treatment. Do not spray evergreens directly with the baking soda but if you are trying to grow grass under them it WILL HAPPEN. The Epsom salts can be used on everything. It is a great fertilizer. The baking soda is more effective than liming and a lot easier to do. A great fertilizer is miloganite for adding nitrogen. For broad leaf control I use Scotts liquid 2 again with the hose. If you use my system you will not need to thatch, it will help to keep bus down, you will not get deseases, and will need to water far less. Cut at least at 2 inches and never cut more than 1/3 of grass blades at a given time. GOOD GROWING

  24. Had a very large oak tree cut down that had green fungus all around the base of the tree .had the stump grounded and we filled the hole with about 50 bags of miracle grow and fertilizer. Planted grass and some of it came up had to reseed it again using the same method. Have done this 4 or 5 times and still haven’t gotten the area to fill in. What do you suppose we can do to get the grass to grow. Have not tried a fungicides yet because I don’t know what kind is best or if it will help. Thought about sod but hate to spend the money and it doesn’t work. What do you suggest??

  25. I live in the Panhandle of Florida and sooner or later you get fungus. It rains a lot here. had fungus two years ago. I treated it and in the fall ripped out the bad parts. I have Saint Augustine and I use baking soda now. No problems anymore.

  26. I am facing of problem in my play ground of brown round shaped patches. They are increasing day by day. The look of play ground going on worst position. The treatment of playground is on date as per prescribed by local agriculture related offices. But the problem remain same. Please suggest us the proper treatment of lawn or ground.

  27. Hi. I live in North Eastern Alberta where we get 7 months of winter. The snow in the yard can last 6 months. Where the snow is deepest, as in where it has been shovelled, or where it has been packed by traffic, I get yellow, straw like patches varying from 4″ tp 12″ in dia. They stay all summer. What can I put on the lawn in the fall to help prevent this? I routinely aerate, thatching doesn’t seem to be an issue. All our soils up here are clay based. I asked at Home Hardware today but they had no clue. Thanks for your help

  28. Good day
    I work at a beauty shop where lots of stray cats come and do there business . I have noticed that orange carrot like something is growing out of the ground. Help this

  29. Have the brown grass fungus , in summer, treated with Dr. Earth Fungicide…worked well but seems have a burgundy fungus, and a large almost square section of lawn that is yellow. I am so frustrated.
    Will eventually go with the baking soda mix as preventative…
    However, will I ever be able to have lawn fungus free? Have had 2 bad years with brown spot fungus on long stem roses, just cut down…treated with 3 in one both years. What does one do? Just want fix. Please help.

  30. How do you mix the soda an Epsom salts mixture. For. black slimy. patches on yard. I live in. Georgia but we have had an abundance of rain.

  31. I have large circular spots in my zoysia, 8 to 10 feet in diameter. Eventually the center grass is restored but it seems to creep outward. What is it? Hoe do I get rid of it?

  32. My grass pulls out easily (rips out at ground level – roots stay in ground. Grass rips / tears breaks off with just a gentle tug.)

    Was a beautiful lawn a month ago.

  33. these are like little mushrooms grey and very slimy comes and go with the weather I have taken 1 metre off top off and there is no sign of any rootes could this have been brough in with new top soil because it only appears to be where the soil has been layed

  34. I live in Maine. We’ve had a very dry summer. I resided my lawn and reseeded it about two months ago. It has looked great….the best in the
    neighborhood….very h. I have just discovered many stems on the edge of my lawn have black on the tips of the grass. This section of the lawn is in the sun. Is this caused by a fungal disease and what can be done about it. Should I wait until spring to do anything as it is almost the end of September?

  35. I have used St Augustin this year to sod my yard. We have had a very wet summer in Mobile. I understand from all the dampness I have a fungus problem. All my grass has died and turned brown. I have used a fungicide but nothing helps. Should I spread a new layer of top soil and start over?

  36. I live in Oregon and have a major fungus problem and a brand-new lawn professionally done with extensive drainage. The work was done beginning in June last summer. Within a couple of months I had lots of mushrooms and then the brown spots started to come and have never stopped. I can’t seem to get a lot of help with what to treat this with as I have a $30,000 investment and it just looks terrible can you help me. The grass was fescue the landscaper keeps telling me it will take care of itself I believe they were negligent in some of their work and any kind of observations by them is so untimely I’m afraid my summer and my beautiful lawn that I paid so much money for is going to be nonexistent. I need to take matters into my own hands and fix it

  37. My son lives outside of Dallas TX him and his 2 children seem to get a lot of sinus and respiratory illness. Can his yard be some of the cause? Last yr when I was their I seemed to smell mold. He says he has treated it.

  38. Hi-Can you identify what going on w/grass? It is rapidly moving.Here’s a pic.I”m in N.Colorado-Thanks so much
    Cant get pic to transfer.Do u accept pics?

  39. I suspect I have brown spot, brown patch, and maybe some dollar spot.
    Couple of questions:
    How do I actually distinguish between the 3; and secondly, what is the #1 bet way to either get rid of it or at least control it for this year and stop it from returning next year.
    I live in the Newport News area of Virginia. My grass is mostly fescue and Bermuda is creeping in (I’m sure there is other stuff mixed in)………… I overseed every fall after aerating)
    Years past my lawn was always a nice deep, dark green, this year I have this fungus. Weeds are not a concern…pretty much weed free.
    Thanks for any info you can give me……

  40. Hi there. First time lawn. Grew in nicely and has great color. A week ago I noticed a large dark patch that looks greasy. Now there are two. Thinking I might have a fungal problem. Brown patch or something. Anyway, was wondering what I can do to quickly rid my lawn of the patches. Thanks in advance!

  41. Why are the questions on your page not answered on this page?It would be so helpful instead of answering the same questions over and over again.

    • Hi, Ellie!
      We can’t answer all the questions we receive, due to the high volume (2+ million monthly visitors), but we sure do our best!
      Selected questions receive a moderator’s answer, as the comments form states.
      Thanks for visiting noppukappo.info.

  42. I live in North west Queensland. Where my lawn is all the soil has slim sitting on top off it even though the grass is green and growing the entire soil is green looking

  43. I had a lawn company treat my lawn 3years ago with liquid spray. Where ever he walked the next two days or 3 days the grass turned brown and died. That was the beginning of my fungus problem. I have done everything, even went to cooperative extension they could not even help. Lawn starts beautiful in spring then you see a light fuzzy brown spot on top of a few blades the size of a 3″ circle , that’s the beginning. It gets larger and larger as the grass dies as if a dog peed on it. Then I start seeing it appear other places. Please no one can help me! There must be someone out there. HELP! HELP!

    • Hi, George,
      That does sound challenging, and unusual! We’re opening this question to the TodaysHomeowner.com community.
      Has anyone else experienced this?

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