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How to Get Rid of Lawn Algae

Lawn algae in brown grass

Lawn Algae is a type of algae that grows in your lawn due to moist conditions. It can be green, brown, or even black in color. If you’ve dealt with it before, you know how unsightly it can be to see in your grass. The best way to prevent lawn algae is to do everything you can to keep it healthy. However, if you’re reading this blog you probably already have it. 

What Causes Lawn Algae?

Lawn algae grow best in areas of your lawn that are hindered by poor growing conditions. These conditions include minimal sunlight, soil compaction, and excess water caused by poor drainage. Algae also grow best in warm and humid conditions. Prime growth time is during the summer, but you may also notice it at the end of spring or beginning of fall.

How to Get Rid of Lawn Algae

The best way to get rid of lawn algae is to:

  • Identify the lawn algae: Before you actually treat your yard or lawn, make sure that it's actually lawn algae and not moss (a weed) growing on your grass blades. Moss looks like thin sheets with small bumps (like fish scales), whereas lawn algae look like fine hairs.
  • Alter growing conditions of your lawn:  Lawn algae prefer nutrient-rich soil, if your lawn is lacking the nutrients algae require, it will be less likely to develop. 
  • Increase water drainage: A healthy lawn should be able to absorb more water than the soil can hold. If you have a soggy lawn, it is because of poor drainage, which adds to the chances of lawn algae growing.
  • Increase aeration: Lawns should not be compacted – this increases their susceptibility to weeds and lawn algae. Aerate your yard at least once a year – this will improve nutrient uptake by your grassroots.
  • Fertilize periodically: Your grass should require periodic feeding throughout its growing season (spring, summer, fall). You should also avoid over-fertilizing, which increases the chances of lawn algae developing.

Is lawn algae dangerous?

Lawn algae are not dangerous to humans or pets, however, they can cause allergies for some (similar to how some people are allergic to seafood). Symptoms of such an allergy include:

  • Runny eyes 
  • Lymph nodes swelling 
  • Itching Throat 
  • Skin rashes

What does it look like?

Lawn algae produce thread-like growth similar to fungi. It is green, brown or yellow in color. It usually grows on grass blades and will either appear as a light coat of mold or be present as thick patches that may look like slimy foam. If you accidentally brush up against it, the lawn algae patch will release spores which can cause respiratory problems for some people. If you need help identifying it or want help with other types of lawn care, give us a call!