Lumps and indentations in your lawn can make manoeuvring around it very difficult, especially when trying to mow the grass. The bumps and imperfections in the ground will snag on your equipment, risking damage and injury while gardening, and these uneven areas can also cause trips and falls. Many gardeners will therefore seek to flatten their uneven lawns.
Flattened lawns are also better for drainage and prevent issues with waterlogging, encouraging water to spread more evenly through the lawn when watered or after rainfall, and boosting the intake of important nutrients.
What Causes Unevenness in Lawns?
There could be a number of reasons why your lawn has become lumpy and out of sorts, but the most common causes include:
- Heavy Foot Fall: Your lawn may experience soil compression due to heavy foot traffic in certain areas, which can lead to unevenness.
- Irregular Thawing: Spring thawing of frozen, dense soil may result in bumps on your lawn due to uneven melting.
- Water Logging: Waterlogged areas with mushy and wet soil can depress and put pressure on the top layer of your lawn, causing it to sink.
- Earthworms: While earthworms can decompose thatch and be beneficial for your lawn, their constant burrowing can create an irregular and uneven appearance, especially in moist soil.
- Digging Wildlife: Keep an eye on animals like cats, dogs, and foxes as they can cause unwanted bumps on your lawn through digging.
- Soil Settlement: Over time, an old lawn may gradually become bumpy and uneven due to soil settlement.
- Gardening Technique: Repetitive patterns from heavy gardening equipment like lawnmowers can cause holes and ruts to develop over time.
Benefits of Flattening Your Lawn
There could be a number of reasons why your lawn has become lumpy and out of sorts, but the most common causes include:
- Improved Aesthetic: One of the most apparent benefits of having a level lawn is that it looks better. A flat lawn with no bumps, dips, or uneven areas provides a uniform, neat and tidy appearance, which enhances the overall look of your garden.
- Easier Maintenance: An uneven lawn can pose a tripping hazard for anyone walking on it, especially children and the elderly. Flattening your lawn will eliminate these risks and make it safer to walk, run and play on.
- Enhanced Safety: Waterlogged areas with mushy and wet soil can depress and put pressure on the top layer of your lawn, causing it to sink.
- Improved Drainage: Uneven lawns can cause water to accumulate in low-lying areas, leading to waterlogging, soil erosion, and other problems. Flattening your lawn will improve drainage and prevent water from pooling in one place, helping to maintain healthy grass growth.
- Better Lawn Health: A flat lawn can benefit your lawn’s overall health. Uneven areas can cause soil compaction, which can lead to poor grass growth and even the appearance of moss. A level lawn allows the grass to grow evenly and prevents water from stagnating in certain areas, reducing the risk of fungal growth and disease.
When Is the Best Time to Flatten Your Lawn?
The ideal time to flatten your lawn is during spring, when frosts have passed and the grass is actively growing again. When flattening, it is advisable to use a mix of sand, topsoil, and compost for top-dressing soil, which fills the desired areas while also enhancing drainage and nutrient-rich soil formation.
Remember to choose the appropriate levelling method depending on the depth of the low spots, whether shallow or deeper than 2–3 centimetres.
What to Do Before Levelling Your Lawn
Before you begin flattening your lawn with one of the techniques outlined below, it is essential that you first check your lawn thoroughly to determine which method will be most beneficial, and identify external factors that could be impacting the state of your lawn, such as damaged water pipes and other underlying drainage issues.
Identify Drainage Issues & Low Spots
Seek professional advice if low spots are found around water pipes, and if drainage issues also exist, it is advisable to re-grade the lawn while levelling it to create a slope away from the property for improved drainage. Alternatively, an underground drainage system can be installed that utilises gravel or flexible drainpipes.
Make Sure Your Lawn Is Pre-Watered
When flattening a lawn, it is essential to check for the depth of low spots to decide which method will work best. The two main methods of levelling a lawn are using top-dressing soil and soil replacement. To prepare for the levelling process, the lawn should be watered several days before to ensure that the soil is not too hard or powdery.
Gather Your Tools
Depending on the flattening method you choose, there are a number of tools you could make good use of, including:
- Aerator: A lawn aerator features spikes that penetrate the soil’s surface to create holes. By doing so, they improve soil drainage and promote the entry of air and water to the grassroots.
- Garden Rake: A garden rake is an effective tool for spreading the levelling mix across your lawn.
- Lawnmower: To begin levelling work, you’ll need to cut the grass short using a lawnmower.
- Levelling Rod: A levelling rod is a simple wooden tool with strings attached to its ends. It helps you identify areas that require levelling by providing a flat surface.
- Shovel: A shovel is useful for digging the lawn and applying the levelling mix.
- Thatch Rake: A thatch rake helps remove the dead and drying layer of grass from your lawn.
- Wheelbarrow: A wheelbarrow is necessary for mixing equal parts of sand and soil, and it helps transport the levelling mix wherever it’s needed.
How to Flatten Low Spots in Your Lawn
1. Wait for Spring or Autumn
To fill low spots in your lawn, it’s best to choose a few mild days at the beginning of autumn or spring. It is recommended to do this about 3–4 weeks before the severe heat of summer or the cold of winter, allowing time for new grass to establish before the weather turns.
Depending on your availability, you can either fill in all the low spots in your garden or work in sections to flatten smaller areas at a time.
2. Check for Drainage Issues or Broken Pipes
Contact your local water department to locate the pipes running beneath your garden and look for areas where water pools up, then have a professional plumber inspect for any damaged pipes. It is essential to have any broken or damaged pipes repaired before levelling your lawn to avoid the formation of low spots again.
If there are no damaged pipes, contact a professional landscaper to determine the source of your drainage issues. Poor drainage can be fixed, and your lawn may alternatively need re-grading to address the problem.
3. Break up Your Soil Mix
To prepare top-dressing for your garden, start by breaking apart the lawn soil in a wheelbarrow. Use a bag of lawn soil that includes sand, soil, and compost, then use a rake to work through the soil mix, breaking apart any large clumps to ensure even distribution across your lawn.
Pro tip: You can mix your own top dressing by combining equal parts of peat moss, topsoil, and sharp sand.
4. Water Your Lawn Well
To help your soil settle and determine the actual depth of the holes that need filling, use a shower attachment on your hose to lightly water the section of lawn you are working on. Ensure that the soil feels soft under the grass, rather than hard and dry. By doing this, you’ll be able to gauge the correct depth of any holes that need filling.
5. Decide Whether to Save or Remove Grass
If the holes in your yard are deeper than 2–3 inches, it is recommended to remove the grass. Leaving deep soil covering the grass can lead to decay and harm your lawn. To check the depth of the holes, measure them and if they are deeper than 2–3 inches, use the blade of a shovel to cut and remove the grass from the surface.
However, if the holes are shallower than 2 inches, it is okay to put soil directly on the grass. If possible, try to save the grass as you may be able to replant it once the holes are filled.
6. Fill the Low Spots
To fill the low spots in your garden, work in small sections of 2–3 square feet across your lawn. Use a few shovelfuls of lawn soil from your wheelbarrow to fill any ruts or holes. Spread the soil evenly across the area, and use the back of your shovel to tamp the dirt into the holes.
Try not to worry if the soil is not perfectly flat as you can level it out later. To get a more accurate view of your lawn’s level, mow the grass as low as possible.
7. Spread Your Soil Evenly
When spreading the soil, utilise a garden rake and alternate between the pronged and flat edges to ensure even distribution. If any low spots are not entirely filled, add some lawn soil and level it out. Keep working the soil over your lawn until the grass blades emerge from the top dressing.
Make sure that the top-dressing layer is less than 1 inch thick since it can be detrimental to your grass if it is thicker. Alternatively, a manual leveller can be employed to smooth out the lawn.
8. Water Soil and Leave it to Settle
To allow the soil to settle, water it generously with either a hose or sprinkler. Give it 1–2 days to compact before checking the level of the soil again. If the soil has settled but the spots are not level yet, it is time to fill the holes once again with more soil.
9. Replant Grass if Necessary
If you had to remove any grass from your lawn, it is essential to replant it. Begin by checking your lawn for any bare spots and attempting to fit the old patch of grass over it. Make sure to tamp it down to ensure the roots have good contact with the soil. If the old patch does not fit, you will need to plant new seeds.
For those who don’t want to wait for new grass to grow, sod is an option. Cut the sod to the shape of the bare spot and press it down onto the soil. It’s advisable to use the same type of grass as before to maintain uniformity.
How to Flatten Your Lawn with a Roller
1. Wait for Spring and Roll Yearly
To avoid soil over-compaction, it is best to roll your lawn annually during springtime. Rolling your lawn more frequently than this can inhibit root growth, so it is important to stick to this schedule. By rolling your lawn in the spring, you can get it ready for the growing season ahead.
2. Water Your Lawn Before Rolling
In preparation for rolling your lawn, it is important to moisten the soil by watering it. To achieve this, attach a sprinkler to your garden hose and allow the water to run for approximately 20–30 minutes. Be careful not to overdo it, as an overly wet lawn will require additional drying time before rolling. This process will make the soil softer and easier to flatten with your roller.
3. Roll Your Lawn in Sections
Fill your roller with water until it is a quarter full, then flatten raised areas of your lawn by pulling or pushing the roller in long strips across your lawn, remembering to take breaks frequently to prevent fatigue. For slopes, work horizontally to avoid uphill struggles.
Add more water to the roller if the yard is not levelling out. You can also reroll certain areas that are refusing to lay flat.
4. Cut Grass if Necessary
To fix large bumps in your lawn, cut the grass and use a shovel to dig out soil from the mound. Peel back the grass around the bump and tamp it down with the back of your shovel to check if it is level with the rest of your lawn, then remove mounds that refuse to flatten out. When you are done, replace the grass or plant new grass seed on the bare soil to replenish the area.
5. Aerate to Finish
To promote the penetration of air and water into the soil, it is advisable to aerate your lawn. Loosen the soil by rocking a garden fork back and forth 4 inches into the ground, and repeat this process across your entire lawn. Aerating your lawn can break up compacted soil, making it easier for your plants to grow. A gas-powered aerator can make the job quicker.
