Why is my lawn turning brown?

Brown (or yellow) patches in your lawn can be really frustrating. If you’re wondering what is causing the problem, we’ve listed the common culprits below, from disease to human error, along with some helpful remedies to address the problem.

Human and animal damage
  • Dull lawnmower blades tear your grass and gradually kill it over time.

    Remedy: Sharpen your lawnmower blades regularly and check that the grass is being cut properly after each use.

  • Scalping happens if your lawnmower blades are set too low or if there are lumps in the grass causing you to cut the grass too short.

    Remedy: Raise your mower blades or dig up the sod and remove some of the soil from beneath before replacing it.

  • Chemicals such as gasoline, fertilisers, insect repellents and pesticides can burn your grass.

    Remedy: Never spray any chemicals on your grass and do not park your car on it.

  • Urine from dogs, cats, birds and other animals can cause your lawn to turn brown or yellow. Sometimes a bright, green ring will appear around the patch where the diluted nitrogen in the urine acts as a fertiliser.

    Remedy: Immediately spray the area with water to reduce the damage. You should also ensure that your pets are well hydrated, as this will keep them healthy and dilute the strength of their urine.

Poor growing conditions
  • Bad soil quality can cause brown, bare areas and moss.

    Remedy: Take a screwdriver and push it into your soil; if it doesn’t slide in easily, your soil may be compacted. To remedy this, you can try aerating and top-dressing to incorporate organic matter in the soil.

  • Buried debris could be lurking beneath your soil, preventing proper growth.

    Remedy: Have a poke around or use a metal detector to identify the problem and dig it up.

  • Erosion occurs on slopes and hills as water rolls down the angle and takes grass seeds with it.

    Remedy: You can aerate your lawn to increase water absorption, or if the slope if steep, you may want to consider building terraces or planting groundcover.

  • Roots of nearby trees and plants may be competing with your grass for water and nutrients, making it hard for the lawn to grow.

    Remedy: Under these circumstances, you could consider mulching or naturalising areas underneath trees.

  • Drought-damage can occur in dry, compacted areas of your garden.

    Remedy: Lawns need about one-inch of water a week, either from rainfall or irrigation – so use a hose or watering can on your lawn regularly or consider installing a sprinkler system.

  • Natural dormancy will occur in the summer if you have a cool-season lawn or in the winter if you have a warm-season lawn. If your lawn is comprised of a mixture of grass types then it may appear patchy.

    Remedy: This is normal but you should ensure your lawn is healthy and strong to prevent unnecessary browning.

Lawn diseases
  • Thatch is a build-up of decaying grass blades that become so thick they choke out the healthy grass.

    Remedy: Remove thatch if it’s more than half-an-inch thick.

  • Fungal diseases thrive in moist conditions, particularly in midsummer when the weather is humid and in spring. You may notice circular or irregular brown spots on the lawn, spotting or infected patterns on the grass blades, or a more general thinning or drying out of the lawn.

    Remedy: Encourage sunlight and air circulation as much as you can. You can take a sample of the affected grass to a specialist for diagnosis and treatment.

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