Lawn Fungus: What Causes it and How to Deal with it?

Lawn fungus could be to blame if you’ve been trying to get a beautiful green lawn, but all you’ve got is a brown, patchy one.

Even though fungal spores are on every lawn and can help your lawn, they can be a big problem when they start to grow and spread.

What’s Lawn Fungus?

  • Lawns are made up of millions of living things called microorganisms that help your grass grow. 
  • Fungus spores are present on every lawn, and for the most part, they’re beneficial. But if your lawn is in trouble and the conditions are right, these spores start to grow and cause problems.
  • Sometimes, lawn fungi are good for some grasses. Why? Because they help in decomposing organic matter that supports good growth. Fungi supply turf nutrients and belong in the turf; if properly maintained, they enhance the wonders of a beautiful lawn.
  • Bad lawn fungus is always there present in the soil, waiting for the right time to be active and ruin your lawn. Like silent enemies, seeking the right time to attack when your turf is already under some stress. 

What Causes Fungus on a Lawn?

  • Fungus is most often caused by too much heat and moisture. As was said above, fungus often grows when plants are under stress, such as during droughts, long rainy seasons, or when they get too much water.
  • The fungus often grows when water sits on the surface of a leaf for too long. Fungi’s “living parts,” called mycelia, use water as a “highway” to move from leaf to leaf. Due to this, the fungus might spread to other grass areas.
  • This is also why you shouldn’t walk on your lawn when it is trying to get rid of the fungus. If the grass is wet, the fungus can spread over the lawn.
  • The fungus can also be caused by not getting enough food. When grass doesn’t have enough of the proper nutrients, it is more likely to get sick.
  • When it rains, the grass plants usually have more water to use in the soil. When plants drink that water, they also drink nutrients from the soil, like nitrogen. The nitrogen is used up faster when it rains. If you don’t replace the nitrogen, the problem will keep happening.

How to Recognize Lawn Fungus?

Lawn fungus can attack your grass in many ways. Brown and patchy spots are just one of them. Here are some signs to spot fungus in your lawn.

  • Round, Pale-Colored Spots:

This is a common sign of snow mold, which you can find in areas with moss. If your grass has some moss, this is a likely sign of a fungus. As soon as the snow melts at the end of winter, this fungus will sprout.

  • Orange-red Spots:

This is a sign of rust disease. You’ll see spots on the grass that look like rust because they are orange and red.

  • Yellow Spots:

Your lawn can get red thread disease, a fungus type. It turns parts of the grass yellow.

  • Dollar Spots:

The size of a dollar coin gives these fungus spots their name. They have a pale color and sink into the grass. When there is a lot of dew and the nights are cool, like in the spring, these spots tend to appear.

Fairy rings” are big circles of brown or light-colored grass. Even though they make a circle, the grass can look healthy and expected within their edges.

Can Lawn Fungus Be Removed?

There are crucial steps you must take if you suspect fungus in your grass. These will help you deal with it better and get rid of it.

  1. Water in the Morning:
  • If you water your lawn early in the day, it will have time to soak up the water and dry off as the day goes on. 
  • Not allowing your lawn to dry completely between waterings will promote fungal growth, so try to avoid doing it at night or very early in the morning. 
  • Fungus moves through the water, so a wet lawn will make it much easier for fungus to spread.

2. Sharpen Mower Blades:

  • When trying to stop fungus, having sharp mower blades is vital for successful mowing. A blade that isn’t sharp enough can tear the grass, making holes where disease can get in.
  • If the mower blades are dull, instead of cutting the grass entirely, its just tears off the top. This results in developing the fungal disease. Why? Because frayed blades of grass are more susceptible to fungus. 
  • Ensure to sharpen the blades before mowing to prevent fungus.

3. Get Rid of Thatch:

  • Thatch, the layer of dead organic matter that builds up on grass, can stop air from getting to the soil. Regular removal, perhaps with a motorized rake, could assist.
  • Dethach is a method where the old grass gets removed manually with a detaching rake. 
  • It is a time consuming process but necessary if you want to prevent lawn fungus. 

4. Help the Air Move Around Better:

  • Many kinds of lawn fungi grow best in damp, shady places. To let more airflow through your lawn, you should trim shrubs and trees that cast shade on it.
  • Proper aeration in the soil helps to prevent lawn fungus. As aeration helps compacted soil loosen up. This is vital as compacted soil compresses the soil and this hinders healthy grass development, reducing drainage and leading to lawn fungus. 
  • Lawns should be aerated once every two or four years to maintain optimum health. 

5. Don’t Walk on Deep Snow:

  • Snow causes mold in lawns. It is called snow mold. If there is a lot of heavy snow in your garden, don’t walk on it. This will pack it down and make it more likely that snow mold will grow in the spring.
  • To prevent snow molding, try to un-pile it after the kids are done making a snowman. If the snow is idle for a while, it will eventually lead to fungus when the winter is over. 
  • If you can’t do it yourself, call for professional help. 

6. Curing Lawn Fungus in the Organic Way:

  • Lawn fungus can be eradicated by natural means. Among these are solutions of neem oil, baking soda, and compost teas. 
  • To get the best results, use these natural options early in the season as a preventative measure instead of waiting until your lawn already has a fungus to treat it.
  • There is broad spectrum fungicide also available for treating many types of fungus. However, do not use the fungicide directly, but take a sample first of the fungi grass for a patch test.
Lawn Fungus: What Causes it and How to Deal with it
Lawn Fungus: What Causes it and How to Deal with it

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Lawn fungus can be hard to get rid of, but as we’ve seen, it’s easy to avoid! Putting these tips into practice now will save you time, money, energy, and, most importantly, stress in the long run.