How to Fix Fertiliser Burn

You fed your lawn expecting lush green growth, but instead you are staring at brown, scorched patches. Fertiliser burn is one of the most common lawn care mistakes, and while it is self-inflicted, the good news is that most cases are fixable. Your lawn can recover fully with the right approach — you just need to act quickly and follow the correct steps.

What Causes Fertiliser Burn?

Fertiliser burn occurs when grass roots absorb more nitrogen and salts than they can handle. The excess salts reverse the natural flow of moisture through osmosis, drawing water out of grass blades instead of into them. The result is dehydrated, scorched tissue that turns yellow, then brown.

The most common culprits include applying too much product, overlapping spreader passes so certain areas receive a double dose, spilling concentrated granules in one spot, or feeding during hot dry weather when your grass is already under stress. Synthetic fertilisers with high nitrogen content pose a much greater burn risk than organic alternatives.

Assess the Damage First

Before you do anything, check whether your grass is dead or merely damaged. Gently pull on the brown blades — if they resist and stay rooted, the roots likely survive and recovery is possible. If they slide out with no resistance, the plant is gone.

Examine the crown, which is the white section at the very base of the plant. If it still feels firm and shows any hint of green, your grass has a fighting chance. Yellowing grass edges without complete browning suggest superficial damage that should bounce back on its own with proper care.

Immediate Action: Flush With Water

Speed is everything. As soon as you notice signs of burn, start watering — heavily. Apply at least 2–3cm of water daily for one full week to dilute the excess nutrients and flush them deeper into the soil, away from the root zone. Early morning watering minimises evaporation and gives your lawn the best chance of absorbing what it needs.

For small concentrated spills, physically remove any visible granules from the surface before flooding the area thoroughly. The goal is to move those excess salts below the root zone where they cannot cause further harm. Our guide to lawn watering covers proper technique and timing in detail.

Recovery Timeline

Mildly burnt grass — where you see yellowing tips but the blades are still firm — typically recovers within 2–3 weeks with consistent watering. You should see green returning from the base of each blade.

Moderately burnt grass, with brown patches but roots that still hold firm, needs 4–6 weeks of patience. Regrowth may appear patchy at first before filling in completely.

Severely burnt patches where the grass pulls out easily and the crown is dead will not recover on their own. These areas need reseeding once the excess fertiliser has been flushed from the soil.

Reseeding Burnt Patches

Wait at least two weeks after the burn before reseeding. This allows the excess fertiliser to leach away so new seedlings are not damaged by the same problem. Rushing this step is a common mistake.

Rake out the dead grass and loosen the top layer of soil with a fork or rake. Scatter seed according to the packet instructions, press it gently into the soil surface, and maintain consistent moisture until germination. Our guide to fixing bare patches walks you through the full process.

Fast Growing Grass Seed is ideal for this job, germinating in just 7–14 days so your repaired areas blend in quickly rather than sitting bare for weeks. When it comes to choosing the right grass seed, matching the blend to your lawn type and sowing season makes a real difference to results.

Preventing Future Burns

Prevention is always easier than repair. Use a spreader for even distribution rather than hand broadcasting, which almost always leads to uneven coverage. Calibrate your spreader properly by testing on a hard surface like a patio or driveway first, so you can see exactly how the granules are falling.

Never overlap your passes. Most spreaders have a shut-off bar for a reason — use it at the end of each row. Follow your recommended feeding schedule and application rates precisely. More is not better when it comes to lawn fertiliser.

Avoid feeding during drought, heatwaves, or in summer when temperatures are consistently above 25°C. Always water thoroughly after applying granular fertiliser to dissolve the product and wash it off the leaf blades and into the soil.

What About Liquid Fertilisers?

Liquid feeds generally cause less burn than granular products because they are pre-diluted before application. However, they are not immune to causing damage — over-concentration or applying in direct sun can still scorch your grass.

Always dilute liquid fertilisers exactly according to the instructions and apply during the evening or on overcast, cloudy days to minimise leaf scorch and evaporation.

Long-Term Lawn Health

A healthy, well-established lawn recovers from burn far faster than a weak or neglected one. If you are new to lawn care, our beginner’s guide to lawn care covers the fundamentals that will help your grass stay resilient.

Start with lower application rates and increase gradually over successive feeds as you learn how your lawn responds. If burn keeps recurring despite careful application, consider switching to a slow-release fertiliser that meters out nutrients over several weeks rather than delivering a concentrated dose all at once.