Top Dressing a Lawn

Author: Stefan Palm   Date Posted: 28 November 2023 

Top dressing a lawn is usually done to level up an uneven surface or to fill in holes however there are some other advantages that you may not be aware of. Find out more about the benefits and how it do it yourself.

This simple yet powerful lawn maintenance task involves applying a thin layer of sand and organic matter over the grass, and its benefits are far-reaching. Let's delve into the numerous advantages of top-dressing your lawn.

Enhanced Soil Structure

Top dressing helps improve the overall structure of your soil. Over time, lawns can suffer from soil compaction due to foot traffic, heavy machinery, or natural settling. This compaction limits root growth and hinders water infiltration. Top dressing with a mix of organic matter and soil amendments enhances soil aeration and drainage, promoting healthier root systems and nutrient absorption.

Nutrient Enrichment

Your lawn, like any living organism, requires essential nutrients to thrive. Top dressing provides an opportunity to introduce valuable nutrients into the soil. By choosing a high-quality compost or specialized top dressing mix, you can replenish depleted nutrients and create a fertile environment for grass growth. This results in a greener, more resilient lawn.

Improved Moisture Retention

With South Australia's temperate climate, water conservation is crucial. Top dressing acts as a natural moisture retainer, preventing excessive evaporation and runoff. The added organic matter in the top dressing mix acts like a sponge, holding moisture in the soil and making it more available to the grass roots. This can be especially beneficial during hot and dry periods, reducing the need for frequent irrigation.

Leveling Uneven Surfaces

Lawns often develop uneven surfaces due to factors such as settling, animal activity, or the growth and decay of tree roots. Top dressing with a levelling mix helps smooth out these irregularities, providing a more even and aesthetically pleasing lawn surface. This not only enhances the visual appeal but also makes mowing and other maintenance tasks more straightforward.

What sort of material is best?

A top dressing mix can consist of a combination of sand, loam and compost. If you’re not looking to level up your lawn, then simply use compost. Make sure you buy one that has been properly made and highly composted.  If you’re looking to fill in low spots, then you’ll need to add some sand or loam to your topdressing. In this case, it’s important to make sure that the texture of the sand and loam you use matches the soil under the lawn as closely as possible, as these new materials will eventually form part of the root zone and will therefore, need to blend well.  Sand or sandy loam is sometimes used as a topdressing material on lawns with heavy clay soils or drainage problems. Usually applied after aerating, the sand fills in the holes and, over time can alter the structure of the soil to allow for better drainage and a healthier grass. You can buy top dressing mix in bags from most hardware stores and garden centres. Check with your local landscape supply yard for bulk quantities.

DIY Top Dressing

Start by mowing your lawn. This will help you spread the top dressing material across the lawn easier and will facilitate in you keeping the top dressing layer as thin as possible.

If you’re top dressing simply for the health benefits rather than to level your lawn, a light layer of around 3mm is what you are looking for. A 20kg bag of top dressing mix would be enough for about 5 square metres. If you’re topdressing to level your lawn up, it’s best to keep the depth of top dressing at no more than 10mm. If you have holes that are deeper than 10mm, you’ll have to top dress in stages, letting your lawn recover between applications.  

Spread the top dressing material in small piles around your lawn and rake them in evenly using the back edge of a rake, or even better, get your hands on a levelling rake like the one pictured here. Once finished, you should see the tips of the lawn poking through the top dressing. Avoid completely burying the lawn, as this will result in it taking longer to recover.  If you haven’t fertilised in a while, now is the time to do it. The last step is to water the top dressing into the lawn. This will help settle it down into the thatch layer.

When do you top-dress?

The best time of year to top dress is from October through to March. You need a good 4 - 6 weeks of warm weather for your lawn to grow through.  When top dressing for levelling purposes, you only need to do that as required. Top dressing with compost can be done every year for good soil and turf health. 



Comments (3)

Top dress

By: on 19 January 2024
Going to dethatch,scarify and top dress and overseed my kykuya lawn due to being very spongy. Would early March be ok or would you suggest wait until oct. What would You recommend 60/40 blend or straight sand???. Regards Stan

Paul Munns Instant Lawn Response
Hi Stan Thanks for your enquiry Optimum time to top dress is from October to Jan/Feb. We recommend using an 80/20 Sandy loam mix and top dress no more than 5-10mm at a time. Andrew

Top dressing

By: on 7 December 2023
Can you top dress kikuyu lawn for uneven spots straight after scarifying it? Looking at doing it in January.

Paul Munns Instant Lawn Response
Hi Georgie Thanks for your enquiry Yes, you can top dress in January after scarifying. Top dress no more than 5-10mm at a time Regards Andrew

Top dress

By: on 6 October 2021
My Santa Ana lawn has dips low areas How to fill and level area Is this the same as top dressing What do I need

Paul Munns Instant Lawn Response
Hi Alan Thanks for your enquiry In the low spots top dress with an 80/20 sandy loam no more than 5mm at a time. Once turf has grown through, repeat process if required Thank you

Leave a comment

Comments have to be approved before showing up