Causes of Yellow Spots on Your Lawn and How to Fix It

There is nothing more disturbing than the sudden appearance of yellow spots on a carefully trimmed green lawn, so what causes the yellow spots on the lawn? Some are natural processes, while others are caused by man-made causes of macula. In this article, we will understand the 9 reasons and fixes of yellow spots on your lawn.

Why are there yellow spots on your lawn?

Yellow lawn disease

Almost all lawns are affected by lawn diseases. Lawn brown spot is one of the most widely distributed diseases among all lawn diseases. Brown spot is a disease caused by pathogenic fungi. It can survive on the soil and can rot in the soil for up to several years, so it is very harmful to the lawn.

How to Fix it

  • Before or during the onset of high temperature and high humidity, less or no nitrogen fertilizer should be applied to maintain a certain amount of phosphorus and potassium fertilizers.
  • Pruning should be done in time, and the mowing in summer should not be too low (generally 5 ~ 6cm). Over-dense lawns should be properly perforated and sparse to maintain ventilation and transparency. Dry grass and residual grass after pruning should be removed in time to keep the lawn clean and hygienic.

Insect pests

Pests are a leading cause of yellowing lawns in many areas. Their thatch on the lawn like to chew the grass roots, causing the lawn to turn yellow .

How to fix it

  • Take out a magnifying glass and look at the blades of the grass to check thoroughly the thatch and insects on the grass. These pests include billbugs or lawn moths etc. Once the pest that damages the lawn is identified, please use the insecticide formulated for the pest treatment.
  • Properly reducing thatch and watering, proper fertilization can also help reduce the number of pests in the lawn.

Lack of water

Hot weather or lawn areas that are completely exposed to sunlight all day will quickly dehydrate grass. If you do not water the lawn frequently enough, the lawn may become dry, fragile, and yellow.

How to fix it

  • One way to solve the drying problem is to water the turf more frequently and as early as possible in the early morning to allow the water in the lawn to dry out after a day.
  • Watering in the morning can also prevent lawn diseases, and watering at night will only waste a lot of water.


The two main sources of nitrogen fertilizer on the lawn are fertilization and dog urine. Nitrogen is a chemical that promotes green leaf growth and is an essential nutrient for dense, healthy lawns. But too much nitrogen will chemically burn grass roots and change the pH of the soil, causing the lawn to turn yellow. Dog urine contains high concentrations of nitrogen, and dog urine in lawns may also burn grass roots.

How to fix it

  • Reduce the number of times the lawn is fertilized. Make sure to irrigate it in deep water.
  • Train your pet to urinate in other places, do not go to the same place repeatedly. Dilute the urine on the lawn with water to minimize damage.

Nutritional deficiencies

Inadequate nutrition can also cause yellow patches on the lawn.

How to fix it

  • Once it is determined that the cause of nutritional deficiencies causes the lawn to turn yellow, you can add a fertilizer rich in iron and nitrogen to the lawn.
  • Please follow the instructions on the package. Too much nitrogen will also cause the lawn to turn yellow.

The lawn was cut too low

If yellow or brown grass spots appear after mowing, it may be because the grass in these areas is cut too short (also known as Lawn scalping). The grass in this area does not have enough water. This is usually caused by uneven lawns.

How to fix it

  • Let your grass grow and provide enough water to grow.
  • Cut the lawn when the lawn is relatively dry and increase the height of the mower.

Soil compaction

The physical damage caused by frequent walking on the lawn can cause the soil to compact and cause the soil to accumulate too tightly, making it difficult for the root system of the lawn to grow and water and other nutrients to penetrate the dense soil. For example, the area where the swing is placed on the lawn or the children ’s playground is mixed with a large number of yellow spots, and it is difficult to grow grass again.

How to fix it

  • Use a core aerator to inflate the lawn, loosen the soil, and then sow and fertilize.
  • Try to avoid crowd activities on the lawn.

Seasonal yellowing

Seasonal changes can cause the lawn to turn yellow. The variety of grass is different. When the seasons change, the lawn will naturally turn yellow.

How to fix it

  • If dormancy turns your grass yellow, you can try using other grass seeds for over-sowing.
  • Wait until spring to let the grass grow naturally and return to green.

Gasoline or Chemicals spilled onto the lawn

Using a gasoline lawn mower, spilled gasoline spilled on the lawn will cause yellow spots on the lawn in the area.

The use of commercial chemical pesticides on the lawn can also burn the lawn and cause macular degeneration.

How to fix it

  • Clean up as soon as possible and dilute the area with water.
  • You may need to excavate this area of the lawn and replant the lawn.


Now that we have identified some reasons of yellow spots on the lawn and how to repair them, how do we restore the bright green? Here are some other tips to revitalize the lawn.

  • Improve the drainage of the lawn to avoid puddles on the lawn.
  • Remove excess grass clippings and fallen leaves to ensure adequate light.
  • Keep the blade of the lawn mower sharp, so that you can trim the lawn when the grass is dry, and increase the height of the lawn mower when mowing in the summer.
  • Fertilize the lawn in accordance with the instructions to avoid excessive use of fertilizers that can cause yellow spots on the lawn.