Fertilisers, Lawn maintenance, Lawn renovation & repair,

How to Restore An Over-Fertilised Lawn: A Step-by-Step Guide

Probably the least-acknowedged cause of yellowing grass! Too much of a good thing is bad! Find out if you're over-fertilising your lawn.

7 MIN 23 Dec
Last update: 01 Feb 2023
Free download
Do you want a lawn calendar?

🌱 All important maintenance moments for your lawn during the year. Leave your email and we will send you the lawn calendar for free.

Enter your email

Receive the lawn calendar in the mail

Enjoy a green lawn all year round!

Having a hard time choosing?
Answer 2 questions about your lawn and we will help you choose the right product!

A lush, green lawn can make all the difference in the look of your home. But too much of a good thing can quickly turn your beautiful, healthy lawn into an over-fertilised disaster. 

Table of contents:
  • Understanding Over-Fertilisation
  • Diagnosing An Over-Fertilised Lawn
  • Treating Your Over-Fertilised Lawn
  • Removing Dead Grass from an over-fertilised lawn
  • Adding Beneficial Bacteria to address over-fertilisation
  • Apply Fertiliser Sparingly
  • Watering Your Treated Lawn
  • Overseeding Your Lawn after over-fertilisation
  • Ongoing Maintenance for a Healthy Lawn

Over-fertilisation can burn your grass and kill off beneficial bacteria, leaving behind a patchy, yellowed lawn. 

Luckily, there is a way to restore your lawn to its former glory., Learn how to fix your lawn after over-fertilisation with our step-by-step guide, and get back to enjoying a beautiful, healthy lawn.

Understanding Over-Fertilisation

Over-fertilised, yellowing grass

What exactly is over-fertilisation, and why does it happen? 

As the term suggests, over-fertilisation results from excessive lawn feeding, causing a build-up of soil nutrients that can lead to an increased concentration of nutrients in your lawn’s water supply. 

This can, in turn, cause a build-up of harmful chemicals, such as nitrogen and phosphorous, which can burn your lawn and kill off beneficial bacteria that keeps your lawn healthy.

Diagnosing An Over-Fertilised Lawn

Graphic showing the nutrient balance of healthy soil
The nutrient balance of healthy soil

If you suspect your lawn is showing signs of over-fertilisation, you could send a sample of your soil away to be tested. However, that can be a slow process. 


These are the symptoms to look out for:

Too much nitrogen (N)

If your grass grows more quickly than you can cut it, you’ve likely added too much nitrogen to your soil. While nitrogen offers rapid and lush grass growth, over-stimulated growth can lead to shallow roots, which lack drought resistance. 

Additionally, too much quick-release nitrogen can scorch the leaf and, in extreme cases, cause the plant to die. On the other hand, a lawn with too little nitrogen looks yellow and thin.

I recommend using a slow-release fertiliser — you’re much less likely to cause scorching or over-fertilisation. 

Too much phosphorus (P)

Phosphorus helps promote root growth, especially in young lawns, and helps build robust and thick turf. 

However, too much phosphorus affects your grass plants’ ability to absorb other nutrients, such as zinc and iron. 

Too much potassium (K)

Potassium helps increase your grass plants’ resistance to disease and drought. 

However, too much potassium causes grass to become pale and lacklustre, affecting your grass plants’ ability to absorb other nutrients, such as calcium, zinc, magnesium, and iron.

Too much magnesium oxide (MgO)

Magnesium oxide stimulates your grass plants’ cellular structure, boosting the green colour by improving the plant’s ability to photosynthesise. 

While MgO helps grass turn green, too much will turn the leaves yellow. 

Get your soil tested

If you’re unsure how much fertiliser you should add, take a soil sample and send it to a lab for testing. This will tell you exactly how much phosphorous and nitrogen are in your soil.

Treating Your Over-Fertilised Lawn

Once you’ve identified and treated the over-fertilisation in your lawn, you can restore it to its former glory. 

Start by mowing, as this helps increase aeration and improve the health of your lawn. Use a weed killer to eliminate weeds growing in your lawn due to over-fertilisation. 

Use the definitions above to identify which type of fertiliser to use. Here’s a table to help you choose a fertiliser to address nutrient deficiency or balance. 

MOOWY productNitrogen (N) — %Phosphorus (P) — %Potassium (K) — %Magnesium Oxide (MgO) — %Iron Sulphate (Fe) — %
2-in-1 Moss Killer and Fertiliser371038
All Round Fertiliser65122
Spring Boost12552
Easy Mow145102
Lawn Starter61082

Once you’ve removed any weeds and cut your lawn, it’s time to fertilise, although it might be a good idea to let it recover for a couple of months before adding more chemicals. 

When you do apply your fertiliser, make it a slow-release formula (like MOOWY’s range) — fast-acting fertilisers can burn the grass. Slowly applying fertiliser will help to restore the nutrients in your soil and increase the health of your lawn. 

If you suspect there are pathogens or pathogens in your soil, you can also add beneficial bacteria to your lawn to help restore its health. You can find these in gardening centres or online.

Removing Dead Grass from an over-fertilised lawn

Using a weed whacker to cut down long grass
A weed whacker in action!

Once you’ve treated your lawn, it’s time to remove any dead grass. Use a weed whacker to cut the dead grass out of your lawn. 

When cutting out the dead grass, leave a one-inch margin. This will ensure the weed whacker doesn’t accidentally damage your healthy lawn. 

Ensure you only remove the dead grass by first flattening the grass with a lawn roller to get a better view of what’s happening in your lawn.

Adding Beneficial Bacteria to address over-fertilisation

Close-up of mycorrhiza

As mentioned above, you can also add beneficial bacteria to your lawn to help restore its health. Use microorganisms like mycorrhiza to create a symbiotic relationship with your grass’s roots. 

This can help reduce the nutrients in your soil and remove harmful chemicals from your water supply, preventing future over-fertilisation and keeping your lawn healthy. 

It can be a good idea to add beneficial bacteria to your lawn while adding fertiliser. Buy beneficial bacteria in garden centres or online. Simply add it to a watering can, and water your lawn to add the bacteria to your yard.

Apply Fertiliser Sparingly

While you should add fertiliser to your lawn each spring to help maintain its health, you should avoid over-fertilising it. 

If your soil test shows you have high phosphorous and nitrogen levels, be sure to apply only a small amount of fertiliser. If you over-apply fertiliser, you risk burning your lawn and killing off the beneficial bacteria in your yard. 

It’s also important to be sure the fertiliser you’re applying is safe for your lawn. Some fertilisers are better for certain grass types, so read the label and use it according to the instructions.

Watering Your Treated Lawn

When restoring your lawn after over-fertilisation, it’s also important to water it regularly. You should water at least once a week, offering a thorough soaking. 

This will help to keep your lawn hydrated and prevent future over-fertilisation. 

If you notice your lawn is turning yellow or brown, it could be that you’re not watering it enough, so be sure to increase the watering frequency. 

Overseeding Your Lawn after over-fertilisation

Easy aerating

Lawn aerating tools!

Quick and simple!

View Products

If you’ve tried restoring your lawn, but nothing seems to have worked, it may be time to consider overseeding, which helps replace the dead grass while keeping your turf young and healthy. 

Before overseeding, aerate your lawn to help the new grass get a foothold in the soil. Use a hollow tine aerator, an aerator roller, or lawn aerator sandals

Once you’ve aerated your lawn, apply a high-quality lawn seed mix and water it in. 

Ongoing Maintenance for a Healthy Lawn

Healthy green grass
Healthy green grass! – Photo by Ochir-Erdene Oyunmedeg on Unsplash

Once you’ve restored your over-fertilised lawn, you’ll want to keep up with regular lawn maintenance to keep it healthy. 

So, create a lawn care plan. 

A lawn care plan can help you stay organised and ensure you’re doing all you can to keep your lawn healthy. When creating a lawn care plan, include regular mowing, fertilising, weeding, and watering. 

If you follow this lawn care plan, you should be able to keep your lawn healthy and prevent future over-fertilisation. 

Any questions?

We hope you have all the info you need to help deal with an over-fertilised lawn. But if you have any questions, please get in touch.

We’re always happy to help. 

Thanks for reading.

What happens if you over-fertilise your grass?

Fertilising your grass boosts the nutrient levels of your soil, which helps create a healthy green lawn. However, over-fertilising has the opposite effect – making your grass turn yellow. Over-fertilising your lawn prevents your grass plants from absorbing the typical balance of nutrients that help them thrive. We recommend fertilising no more than 3 or 4 times a year.

What are the signs of over-fertilising?

The most obvious sign of over-fertilising your lawn is yellowing leaves and a generally lacklustre appearance. Over-fertilisation is probably the least-acknowledged lawn care problem. We recommend fertilising at least three times a year, but no more than four!

How do you restore an over-fertilised lawn?

Firstly, stop fertilising, giving your lawn a chance to recover. Remove any dead grass, then overseed with a high-quality lawn seed mix. Water well, then slowly re-introduce fertiliser after a month or so.

Find the best match for your needs in no time!
Answer 2 questions and we provide you with the best product.
We help you to choose your best product
Question 1/2
Loading your result…
  • What is your lawn care goal?
    1. A. Greener grass
    2. B. A more lush, dense lawn
    3. C. Bald spot repair
    4. D. Lawn restoration
    5. E. Laying out a new lawn
    6. F. Combating moss
  • For which season?
    1. A. Spring
    2. B. Summer
    3. C. Autumn
    4. D. Winter
  • Describe your lawn:
    1. A. My lawn has shaded areas
    2. B. My lawn is used intensively (e.g. by children & pets)
    3. C. I have a decorative lawn
    4. D. I have a standard lawn without special features
  • How many bald spots do you have?
    1. A. A lot, my lawn looks like a barren wasteland
    2. B. A few bald spots here and there
  • Describe your lawn restoration goal:
    1. A. I want to completely renovate my lawn
    2. B. I want to overseed my existing lawn
  • Describe your lawn:
    1. A. My lawn is shaded
    2. B. My lawn will be used intensively (e.g. by children & pets)
    3. C. I would like to have a decorative lawn
    4. D. I would like to have a thick and strong lawn
  • How bad is the moss problem in your garden?
    1. A. Bad. My lawn is covered in moss.
    2. B. Just a few spots
Here’s the product that suits your goal best
Try this one.
< Try again

Comments (0)

There are no comments yet. Well then, what are you waiting for to
inaugurate this pretty page?

Be the first to write your comment!
+ Load more

Do you have some comments?


+Best sellers

Our most popular products

Browse Best Sellers
Scarifying Kit 4.6 (14 reviews) All products after scarifying | Quickly restores the lawn after scarifying | Outsmart weeds quickly with the use of this kit From: £ 39.99
Spring Lawn Care Kit 4.8 (6 reviews) MOOWY’s choice for the spring | Quick recovery of your lawn after winter | A strong lawn prevents weeds From: £ 25.99
Long Lasting Lawn Fertiliser 4.3 (22 reviews) Effective for 90 days | See results in 14 days! | Suitable for all types of grass and soil From: £ 13.99

Free download
Do you want a lawn calendar?

🌱 All important maintenance moments for your lawn during the year. Leave your email and we will send you the lawn calendar for free.

Enter your email

Receive the lawn calendar in the mail

Enjoy a green lawn all year round!