Top dressing a lawn: how and why
Top dressing a lawn is the process of applying additional materials to the surface of a lawn for many purposes and benefits, but most importantly to make it look its best, allowing you to enjoy those beautiful summer days in a stunning garden.
A top dressing consists of a mix of materials such as sand, soil, peat and loam, which should be made to closely match the composition of the existing soil, as all of the new materials will eventually form part of the root zone (soil where roots grow best) and will therefore need to blend well.
What does lawn top dressing do?
Top dressing does not just improve the look of your lawn, but can also benefit the health of the grass too. It allows you to maintain a true and level lawn surface by filling in any imperfections or hollow areas to create a smooth surface. It also helps to dilute thatch layers, assisting in their natural breakdown and preventing them from building up.
For lawns that suffer from water logging a sand based top dressing applied after aeration can improve the drainage and firm the surface as a preventative. Alternatively for lawns with the opposite issue, where drought is a problem, the same method can be applied but using a peat top dressing instead of sand.
The addition of nutrients being introduced from some of the dressing materials can also contribute to improving the fertility of the lawn, encouraging the production of fresh healthy shoots and improving the soil structure of the existing root zone.
When is it best to top dress your lawn?
Ideally top dressing your turf will take place after some method of renovation has taken place, with the most common type being aeration. This is the process of creating holes in the lawns surface to allow stale carbon dioxide out of the soil and oxygen rich air back in. This will stimulate and encourage root growth and can be done with a mechanical aerator or manually with a garden fork.
It is recommended to aerate your lawn once annually, removing plugs of soil from the ground and leaving channels for air water and the top dressing to mix in. Aerator holes are recommended to be roughly 8cm deep, 2cm in diameter and spaced up to 8cm apart.
Be sure to clear any debris such as fallen leaves from the lawns surface before beginning the process in order to allow light and oxygen in and reduce stoppages.
How to top dress your lawn
Make your lawn top dressing
Once the turf has been cleared and aerated the top dressing will need to be prepared. As mentioned this can consist of a mix of materials depending on the existing soil composition and health, such as: sand, loam, topsoil or peat. Any sand used should not contain lime (do not use builders sand) and all ingredients should be dry and sifted before use to remove any large clumps. Alternatively you can buy a ready-made top dressing such as Miracle-Gro EverGreen Lawn Dressing.
Before the top dressing can be applied the grass will need to have been recently cut to allow the dressing to penetrate the existing topsoil without causing damage to the grass. After cutting, walk around the lawn raking and loosening bare patches.
Applying your lawn top dressing
When you are happy with the consistency and ratio of ingredients, you are ready to start applying top dressing to your turf. It is easiest to work a few feet at a time making sure the mixture is spread evenly across the whole surface. The best technique to evenly distribute the mixture is to use both sides of a heavy garden rake, gently working the mix into the aeration holes with the tine side, and spreading it out with the flat side.
The top dressing should preferably be no more than a couple of centimetres in depth, allowing the tips of the blades of grass to be visibly poking through.
Once you have completed the application the lawn will need to be watered and if required lawn starter and seeds applied to replenish any bare areas. For any badly damaged lawns the process can be repeated regularly with light applications.
Allow the top dressing to settle for a few days before gently running the rake across the surface to smooth out any developed bumps or hollows.
Steps to top dressing your lawn
- Clear the turf and aerate.
- Mow the lawn.
- Apply the topsoil, spreading evenly a few feet at a time.
- Water the lawn.
- Rake and smooth any uneven areas.
Now you are ready for the next stage: seeding your lawn.
Seeding your lawn
You can apply grass seed to your lawn either before or after you top dress it. We would recommend that you seed your lawn after you have applied your top dressing. This is because you avoid compromising how evenly spread your grass seed is. Some literature will say that you can mix seed in with your top dressing but this can result in uneven and unnatural looking grass growth.
Now all that’s left is to sit back, relax and watch your lawn transform into a beautiful, fresh carpet of vibrant green!
Check out our video tutorials for how to achieve a great looking lawn on our YouTube channel here.
For tips on maintaining your beautiful lawn please see our 7 lawn care tips