How to lift lawn dips and sunken patches
Lawn dips and sunken patches can be frustrating, especially if you have a strong and healthy lawn. But luckily, sunken areas in your lawn are easy to fix.
While the appearance can be the main reason behind fixing the lawn, there are other reasons to be considered.An uneven lawn can be much harder to mow and can fill with puddles quickly when it rains, which will result in waterlogging and further damage. It can even be a potential trip hazard to you during garden walks or playing games.
Repairing lawn dips isn’t difficult as long as you take your time to work on it carefully. But first, let’s take a closer look at how the dips can be created. If you understand the main reasons they appear, it might be easier to avoid the same mistakes in the future. One thing to remember is, the finer you want your lawn to be, the less forgiving it will be towards any abuse.
Below are the main reasons for creation of lawn dips and sunken patches:
- Heavy foot traffic
- Heavy machinery
- Soil settling down
- Waterlogging
Heavy foot traffic
If your lawn is your pride and joy, we don’t advise any heavy foot trafficking including parties or ball games. Repeated trampling is never beneficial to a fine lawn and smaller dips will be created over a short period of time. Not only will this make it harder to mow, but it can lead to potential trip hazards.
Heavy machinery
It can be tempting to purchase a ride-on mower to make your life easier and to save time mowing the lawn. However, use of a ride-on mower will create tracks when following the same line repeatedly. This especially applies to a well irrigated lawn.
Furthermore, when following the same sunken trucks, the mower deck will lower itself naturally. This can result in damaging the lawn or even your mower, leading to a costly repair.
Soil settling down
Soil settling down can be, and often is, influenced by foot or machinery traffic. This mostly applies to lawns laid on a thicker layer of new topsoil. In a thick layer of topsoil, a massive quantity of air pockets is present. When these are compressed, an extra space is created for the topsoil to settle down, which results in soil sinking.
Tip: use a heavy duty lawn roller when preparing the soil or laying the turf.
Waterlogging
Waterlogging is the final element that can contribute to lawn sinking, simply because it doesn’t usually appear until the first dips are created. When the dips in your lawn are constantly filled with water, the remaining air pockets become waterlogged. As the water pushes the air out, this leads to an eventual air disappearance and, therefore, further soil sinking. To prevent this you should keep your lawn well aerated by spiking to prevent water build-up especially in the winter.
As we mentioned earlier, repairing your sunken lawn doesn’t have to be a difficult task and there are three ways to achieve this.
- Lift dips instantly
- Top-dress the dips once or repeatedly until the level is met
- Top-dress and reseed
You can lift your sunken lawn easily by following these 6 simple steps
- Make sure the soil is moist, if not water well and let it drain. Dry soil could result in tearing the turf later in the process. Cut around the dipped area with a spade – make sure to cut where the lawn is still level. You can mark squares or rectangles, but always leave one side of the dip uncut.
- Lift out the lawn from underneath – ideally, you should dig out a layer around one inch thick or less. The thicker the layer, the harder the work. Then start lifting the lawn opposite the uncut site and gradually move towards it. This should be done slowly and carefully to prevent damaging the turf.
- Roll the lifted lawn towards the uncut edge and leave in place. You can do this gradually.
- Rolling the lawn will uncover the hole in the soil. Fill and level the dip with topsoil – feel free to use any excess soil already in your garden. Press down the soil as tightly as you can.
- Roll the cut lawn back into place. Make sure the edges are in line and pressed down carefully.
- Thoroughly water the area until the roots regrow, taking extra care with the edges. If the edges dry out, they can shrink and create gaps in the lawn.
Watch our free video below.
Top-dress the dips once or repeatedly until the level is met
We generally recommend this approach if the dips are quite shallow, not deeper than half an inch, but you can lift the lawn gradually if the dips are deeper. A thicker layer of topdressing will suffocate the existing lawn.
To fill the dips, this is the only time we advise use of sand instead of a topsoil. The sand is more compact, meaning that the new level will be maintained more efficiently and will not sink again.
Of course, you could apply a smaller quantity of grass seed here to be on the safe side, but regular watering would most likely create a paddle here, washing all the seeds down towards the centre.
The lawn will re-establish itself and the grass roots will develop in the new layer of sand in a month or two, depending on the growing season period. When your lawn patch is fully re-established, you can refill the dip again if you haven’t met the desired level.
It’s worth noting that as the sand tends to overheat on hot summer days, we recommend watering the repaired area daily to prevent any damage. This technique can be used all year round but works better during the active growing season.
Top-dress and reseed
This technique is ideal to repair large or deeper sunken places of your lawn. This time we recommend using a good quality topsoil that has all the necessary nutrition needed to repair your lawn.
You should fill all desirable areas with topsoil to the top and press down by trampling on the area or you could use a garden roller. You will find that the new soil layer will drop slightly as you are eliminating the air pockets. When this happens, apply more topsoil and keep repeating the process until the desired level is met.
Now simply scratch the topsoil with rake and apply the grass seed as recommended on the packaging. You can increase the volume if in doubt, but the calculated amount usually covers all bases including seeds eaten by the birds.
After the seed application, some gardeners advise raking seeds in the soil, but we don’t feel this is necessary. However, the seeds need a firm contact with the soil. This can be achieved by using a roller or gentle trampling. Please note that you shouldn’t do this if the soil is wet or moist as most grass seeds will stick to the roller or your boots and will be removed.
The best time to use this technique is March/April through to September/October as the air and soil need to be warm enough for the seeds to germinate. Be sure to water the patches well.
While the appearance of lawn dips and sunken places can be frustrating, their repair doesn’t have to be a difficult task. Use any of the three techniques listed above to restore your once vibrant lawn.
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