Top Dressing a Lawn

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 use sand or sandy loam. 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 healthier grass. You can buy top dressing mix in bags from us and most hardware stores. Check with your local landscape supply yard for bulk quantities.

DIY Top Dressing

Start by mowing your lawn. This will make spreading the top dressing material across the lawn easier and will facilitate 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 3 -5 mm is what you are looking for. A 20kg bag of top dressing mix would be enough for about 3-5 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.