Lawn topdressing: Why, When and How to do it

Eden discusses the reasons to topdress your lawn, the best time to topdress your lawn and how exactly to do it in this article. Let’s start with the reasons to topdress your lawn.

Why Top Dress Your Lawn?

There are various reasons why you should topdress your lawn, and Eden lists all of them below. 

• Topdressing a lawn improves soil aeration: The compost present in the topdressing material contains microbes that break down the soil and improve soil aeration.
• Topdressing helps break down thatch: The microbes present in the compost also feed on thatch which helps break it down and prevent thatch buildup.
• Topdressing improves overall soil quality: Topdressing improves the overall quality of soil by increasing the soil’s ability to retain water and nutrients. 
• Topdressing aids in leveling the lawn: If there are uneven spots in your lawn caused due to soil erosion, topdressing these areas helps to bring the low spot to the same level as the rest of the lawn.
• Topdressing corrects nutrient deficiencies naturally: The microbes present in the compost break the compost down to make the nutrients available to the soil.

When is the Best Time to Top Dress Your Lawn?

The best time to topdress your lawn is when the grass is actively growing. The topdressing process can temporarily stress the grass as topdressing is usually done over an existing lawn. Therefore, topdressing your lawn when your grass has optimum conditions to grow will help your grass recover faster from the stress and give you a lush and healthy lawn as a result.

For warm-season lawns, the best time to topdress is during late spring or early summer, and for cool-season lawns, the best time to topdress is during late summer or early fall. 

How to Top Dress Your Lawn

There are two methods to topdress a lawn – top dressing by hand and top dressing using a drop spreader. Eden gives the step-by-step procedure for each method below.

How to Top Dress Your Lawn by Hand

Do a soil test: Before you top dress your lawn, do a soil test to determine your soil pH and if your soil has any nutrient deficiencies. If you find any issues in your soil, make appropriate amendments to fix these problems before you begin topdressing.

Mow the lawn: Mow your lawn short enough that the grass does not block the topdressing mix from touching the ground below. When mowing the lawn short, remember not to cut off more than one-third of the grass at a time, or you will stress your grass and cause scalping.

Dethatch your lawn: Thatch buildup can block the topdressing material from mixing with the soil below. Break up any thatch that has built up on your lawn to allow the topdressing mix to penetrate the soil surface. Collect the thatch you have removed using a leaf rake to ensure the lawn is debris-free.

Aerate the lawn (if required): If your soil texture is poor (heavy clay soil or sandy soil), then you should core aerate your soil before top dressing to ensure the topdressing process produces the results you desire.

Mix/Pour your topdressing material in/into a wheelbarrow: Once your soil is prepared, pour the topdressing materials you want to use as a mix into the wheelbarrow in a predetermined ratio. 

Spread the topdressing mix over the lawn with a shovel: Scoop the topdressing mix from the wheelbarrow using a shovel and fling it over the lawn.

Rake: Slightly rake the topdressing material to ensure an even spread that is free of any clumps. You can use a landscaping rake for this purpose.

Work the topdressing mix into the ground: Using a stiff brush, work the material into the ground while brushing the grass blades back and forth with a push broom to ensure they are not buried under the topdressing material.

Spread the grass seeds (optional): Fling some grass seeds over the area, try to be as even as possible to reduce competition between the seedlings that will germinate. 

Water the area: Water the area with a garden hose or a sprinkler till the entire area is moist. If you have spread grass seeds, make sure you don’t drown them. Follow the irrigation pattern of planting a new lawn for the overseeded area.For more information on how to overseed, read Eden’s article.

How to Top Dress Your Lawn Using a Spreader

Eden has given the entire process below.

• Do a soil test: Before you top dress your lawn to determine your soil pH and if your soil has any nutrient deficiencies, make appropriate amendments to fix them.
• Mow the lawn: Mow your lawn short enough that the grass does not block the topdressing mix from touching the ground below. 
• Dethatch your lawn: Break up any thatch that has built up in your lawn to allow the topdressing mix to penetrate the soil surface, and then collect the removed thatch using a leaf rake to clear your lawn of any debris.
• Aerate the lawn (if required): Soils with poor texture (heavy clay soil or sandy soil) should be core aerated before top dressing to ensure the topdressing process is effective.
• Mix your topdressing material in a wheelbarrow: Pour the topdressing materials you want to use as a mix into the wheelbarrow in a predetermined ratio and mix thoroughly. 
• Scoop the topdressing mix/material into the spreader: Using a shovel, scoop the topdressing mix from the wheelbarrow into the spreader. If you are topdressing with a single material, you can directly pour the material into the spreader; you don’t have to use a wheelbarrow in that case.
• Apply the topdressing mix to the lawn: Push the spreader at an even pace to apply the topdressing material to the lawn, like you would push your lawnmower while mowing. 
• Rake: Once you have applied the topdressing mix to the entire lawn, rake it to spread it evenly and to work it into the ground without leaving any clumps of material lying around on your lawn.
• Spread the grass seeds (optional): Fling some grass seeds over the area by hand or spread them using a spreader; try to be as even as possible to reduce competition between the seedlings that will germinate. 
• Rake again: Slightly rake the topdressing mix over these seeds to ensure proper contact with the soil and to protect them from being snatched away by birds or getting washed away due to rain.

What are the Tools Required for Topdressing?

Every landscaping requires the right tools for a smooth and efficient process, including topdressing. Eden lists the tools you will require to topdress your lawn below.

• Soil Test Kit (optional): Test your soil using a soil test kit before you topdress so that you can correct any deficiencies you find. 
• Lawnmower: A lawnmower is required to mow your lawn before you topdress.
• Dethatching Rake: A dethatching rake is required to remove thatch from your lawn before you topdress the lawn.
• Leaf Rake: A leaf rake is required to collect the removed thatch to remove it from the lawn.
• Topdressing Material/Mix: Topdressing materials like sand, topsoil and compost or a blended mix of the three is essential for topdressing.
• Wheelbarrow: A wheelbarrow is required to mix the topdressing material if you are applying a blended mix.
• Shovel: A shovel is required to scoop the topdressing mix from the wheelbarrow and fling it onto the lawn.
• Stiff Brush: A stiff brush is required to work the topdressing mix into the ground.
• Push Broom: A push broom is required to bush the grass blades back and forth while working the mix into the ground to keep them upright and prevent them from being buried underneath the topdressing material.
• Spreader: A spreader is required if you want to apply the topdressing material with a spreader instead of by hand.
• Grass Seeds (optional): Grass seeds are only required if you want to overseed your lawn while topdressing.
• Irrigation System: An irrigation system (garden hose or a sprinkler system) is required to water the top dressed area to ensure the material settles well and to irrigate the grass seeds if you overseed the lawn.

Factors to Consider when Choosing the Best Top Dressing Material

Topdressing material is not a one-size-fits-all type of material. Therefore, you should choose your material carefully for the best results. Eden lists the factors to consider when choosing the best topdressing material below.

• Your Soil Type:. If your soil has a heavy clay content, compost will be the best topdressing material for you; for sandy soils, a blended mix of sand, topsoil, and compost should be used, and for loamy soils, a mix of compost and topsoil will be the best for topdressing.
• Soil pH: If your soil pH is in the correct range, then the pH of your topdressing material should be neutral not to change your soil pH, but if your soil is too alkaline or acidic, then the topdressing material should contain elements like sulfur or lime to lower or raise your soil pH.
• Topsoil Grade: The grade of topsoil tells you the soil particle size or how fine the topsoil is. The grade of the topsoil you use for topdressing should be similar to the grade of your existing soil. For regular home lawns, a double screened ¼ inch topsoil works well. 
• Weed Seeds: Your topdressing material should be free of weed seeds; this is an absolute must. You should consider this factor, especially if you are using compost as a topdressing, as weed seeds are very common in compost piles. 
• Dryness: It is difficult to work with wet material as it creates clumps and does not spread easily. 

Tips for Top Dressing your Lawn

Top dressing is a labor-intensive process, and you don’t want to have to do it more than once because you did it wrong the first time. Eden lists some pro tips to ensure you successfully top dress your lawn in the first go.

• Combine topdressing with cultural practices like overseeding to get a lush and healthy lawn as a result.
• Ensure you topdress at the right time according to your grass type. For cool-season lawns, you should topdress in late summer or early fall, and for warm-season lawns, you should topdress in spring or early summer.
• Ensure your topdressing material, especially compost, is free of weed seeds before you apply it to your lawn. Screen your topdressing mix or use a sterilized topdressing material so that you don’t unknowingly introduce weed seeds into your lawn.
• Make sure the particle size of the topdressing mix is the same as your existing soil so that it can integrate properly.
• Ensure that your topdressing layer is thin (not more than half an inch) so that you don’t bury or smother the grass underneath.

How Often Should you Topdress your Lawn?

You can topdress to fix bare spots or low spots in your lawn as often as required. If you are topdressing your entire lawn, you should not do it multiple times a year as it will increase the grade of your yard and cause leveling and drainage problems. 

If you want to topdress your lawn to revive dead spots or to level uneven lawn spots, contact Eden. Our professional topdressing service will ensure all the requirements of your lawn are met and give a new lease of life to any bare spots in your lawn, resulting in a fully lush and healthy lawn.