Lawns typically give more than they take. Give your lawn a boost with topdressing! Sprinkle a thin layer of fresh, rich soil on the entire lawn.
Topdress will help a lawn recover from soil compaction, nutrient deficiency, and water or heat stress. Grass will grow into a picture-perfect expanse that will let you truly enjoy your garden.
- Read also: What is topdressing?
Topdressing is the perfect way to increase lawn health and beauty in an organic garden without using any chemicals or synthetic fertilizer.
How to topdress a lawn
Steps for topdressing a lawn
Here are the steps to topdress a lawn properly.
- Work on a dry day. Ideally, it shouldn’t have rained for a few days.
- Mow the lawn first, cutting the grass rather low. If needed, dethatch, too (if thatch is deeper than your nail when you stick your finger in it).
- Compute how much topdressing mix you need. From 1 to 8 pounds (½ to 4 kg) may be needed per square yard/meter (see below).
Then, there are three passes you have to run over your entire lawn.
- In the first pass, lump the fresh topdressing mix very regularly around the garden. As a result, the yard should seem dotted with molehills every couple feet (half a meter or a meter apart).
- In the second pass, spread the lumps out evenly and break up any clumps to small bits.
- In the third pass, rake or brush the grass so that the topdressing falls through the blades of grass, and gently bring the blades of grass out top.
At the end of the day, you can water the lawn lightly (no flooding or runoff) to further help the topdressing trickle down to ground level. Don’t mow for at least three or four days. No need to use a roller.
Depending on the surface you need covered, different types of equipment are recommended.
Manual lawn topdressing
In its simplest form, you can just use a pail and a rake. A wheelbarrow might help carry bags of topdressing mix around.
- This is suitable for lawns smaller than 50 square yards or meters.
- Use the backside of the rake for the pass where you spread the topdressing.
- Use the tooth side of the rake to pull up blades from under the topdressing. A specific tool exists which is called a lute. A brush with stiff hair will work best as regards grass health, but it’s longer.
Alternatively, you can directly thrust the topdressing mix on the lawn with a wide shovel (such as a snow shovel). It’s hard, physical work, though. It takes practice to cover the lawn evenly.
All in all, for smaller surfaces, it really isn’t necessary to purchase expensive equipment.
Topdressing with small equipment
- Small hand-powered push topdressers have a hamper. Load the topdressing mix in the soil, and criss-cross across the entire lawn. It’s often the same tool that’s used to spread seeds when re-seeding a lawn. Gravity and spinners that turn together with the wheels spread the mix evenly.
- New electric battery-powered topdressing dispensers have whirring blades that project topdressing mix around. Getting the hang of it is very easy. Spreading the topdressing is also very even.
- Other DIY solutions include rollers made from medium-mesh wire (about ¼ or ½ inch holes, .75 to 1 cm gap) which you fill up and drag or push along the grass, drilled barrels, etc.
Usually, this equipment both spreads and breaks clumps up. As a result, you’ll only need one pass with the device. A second and last manual pass with the rake will pull grass blades up top.
For larger gardens, over 500 square meters or yards, it’s almost mandatory to use motorized devices. The extreme is golf course care, where specific tractors and modified trucks have been designed for the purpose. Smaller variations of these are self-propelled dispensing wagons you guide around the lawn.
Most often, a simple attachment to your regular tractor lawn mower or rototiller will do the trick (tow-type dispensers). Check with your tractor brand to see what accessories are best suited to topdressing.
- topdressing dispensers are usually the same as seed and fertilizer dispensers.
- wide brush accessories will be suitable for raking, as should be done after spreading the topdressing mix.
Best topdressing to use on a lawn
Check for imbalances and compensate
As a rule of thumb, the goal is for the topdressing to be close to the original soil, but tending to “improve” it. This means reaching a soil that is richer, less compact, and better draining. However, it’s important not to be too different from the original soil. The key here is avoiding a certain form of transplant shock.
If you’re only adding a single type of amendment (for example, river sand), then divide amounts by half.
Another option is to prepare a half-and-half mix of new amendment with original garden soil.
Best materials for topdressing
- compost – provides the highest amount of nutrients both short-term and long-term. Best if the composting process brought the compost to high temperatures (over 140°F or 60°C) because this eliminates weed seeds and possible pests. Great for microbial flora and fauna (“live soil”).
- manure – dry manure must be shredded small enough that it won’t form clumps. It’s very rich in microbial life, which is excellent for lawn soil. However, it might give the air a hearty twang for a couple weeks, smelling a bit unusual.
- seaweed – now quite common, seaweed can be a great addition to lawn soil because it has lots of nitrogen. If you harvest your own, rinse and dry it well to eliminate sea salt before shredding it.
- topdressing with sand – best is river sand or quarry sand. Do not use seaside sand because the salt would kill your lawn (quarry sand, even though it was on the seabed, usually has had all the salt washed out over ages). Prefer coarse sand to fine sand. Sand will increase drainage and enhance soil structure. However, in most cases, it isn’t necessary to topdress house lawns with sand, most often only golf courses apply sand turf.
- peat – not recommended in its natural form unless soil acidity needs to be increased. Best prefer new equivalent nature-friendly alternatives like Brière black soil or materials derived from plant or wood fiber.
- topsoil – usually available in horticulture stores
- garden soil – great to add to the mix, especially the first year. Indeed, it’s the best way to ensure topdressing and soil compatibility.
- forest soil – almost as rich as compost, but must be sieved to ensure no large leaf and stick pieces remain.
- used coffee grounds – actually an excellent, ready-to-use lawn topdress. It’s already small enough that it doesn’t need sieving. Used coffee grounds aren’t acidic so it won’t change the pH. And nitrogen content is naturally high, perfect for grasses.
Quantity of topdressing and proper lawn topdress amount
There are two different cases that can help determine the amount of topdressing you need to spread. How often a lawn needs topdressing depends on the situation.
- Regular maintenance of an already healthy lawn – every 3 years – Use 1 to 2 pounds per square yard (½ to 1 kg per square meter). The lower amount guarantees that the lawn will remain beautiful since the layer is almost invisible. It can be repeated up to 6 times within the year. The higher amount makes the lawn look slightly darker or dirtier for around a week. Thicker topdressing should only be applied 3 times that year.
- Regenerative work to heal a lawn that’s in a pitiful state – yearly topdressing until solved, then every 2 or 3 years – Use 6 to 8 pounds (3 to 4 kg) per square meter in lumpy areas and wherever there are holes and bare patches. Use less on “hills” and more in “holes”. Apply 2 or 3 times within the year at most.
When to topdress lawns
Topdressing isn’t always necessary. However, there are situations where it helps grow a healthier, nicer lawn.
Season and time for topdressing a lawn
Best is to topdress just before a growth spurt. Here are the best seasons for topdressing :
- beginning of spring
- middle of spring (a typical June garden task)
- end of summer
- middle of autumn
Don’t topdress lawns in summer or winter. Indeed, slow growth means grass can’t grow atop the new layer, resulting in patches being smothered.
Morning dew, and moisture at dusk, make it harder to topdress. Best is before and after lunch or over the afternoon.
Topdress to replenish nutrients, yellow grass and bare patches
Some spots in the lawn tend to wash out nutrients with runoff. Usually grass on these patches turns yellow, sparse and bare.
- Select topressing that contains good nutrients for grassy plants, high in nitrogen.
- Compost can be used directly.
- Mix in manure or seaweed derivatives.
Here is a before and after shot of topdressing a yellow spot on a lawn:
Vulnerable lawns need topdressing
Lawns that are in the following situation deserve regular topdressing:
- high foot traffic – helps reduce soil compaction
- high sun and/or wind exposure – helps conserve moisture and reduce water needs
- previously a construction work site – fine dust from building materials makes soil heavy
- nutrient-poor soil – lawns set up on thin layers of topsoil, urban areas
- old lawns planted a long time ago – constant mowing has removed organic materials and compacted soil
- lawns not irrigated – drought-resistant varieties like kikuyu grass will benefit from topdressing
Topdressing to help level out bumps and holes
Holes and shallows where old tree stumps were removed can be filled in during topdressing. Similarly, a bump in the lawn can be smoothed out by topdressing around the bump (but not on it).
Topdressing after dethatching, renovating and aerating
You could say that topdressing is like dressing a wound. When a lawn is stressed because of moss removal or the soil was aerated, topdressing will help it heal.
- Dethatching, usually associated to moss removal, is the fact of breaking up the layer of lint that forms after repeated mowing. Blades of grass fall but don’t decompose fast enough. Soil suffocates and only moss keeps growing. Also called scarification.
- Lawn renovation is a set of steps that helps rebuild an old or damaged lawn.
- Aerating the soil means pulling out plugs at close intervals or walking around with nail-equipped shoes. It breaks the crust and helps air and water trickle in.
- Reseeding the lawn or overseeding – spreading new seeds for a more dense, lush lawn. This is either with the same grass as earlier, or because you’d like to introduce a new type of grass. In the end, the variety most suited to the area will win over.
Note: if you’re adding new lawn seeds:
- during maintenance topdressing – spread seeds first, before topdressing
- during regenerative topdressing – spread seeds after spreading the topdressing but before raking it down
Benefits of topdressing for a lawn
- Replenish nutrients in the soil – fresh nutrients and organic matter replaces what has been consumed or washed out.
- Increased porosity, reduced compaction – soil develops small cavities that help grass roots grow quickly. Soil structure is improved.
- Greater air circulation – plants breathe with their roots, too. Microscopic animals, insects, and worms find it easier to breathe.
- Better water retention – small cavities retain water, the topdressing acts to block evaporation. Soil stays cooler throughout the day.
- More biodiversity in the soil – animals have more food, air and water and in turn produce more nutrients for grass.
- Ground is softer and less hard – the layer of living grass is thicker and bounces back after being trod on.
- Less need for fertilizer – organic material in the topdressing breaks down into basic plant nutrients.
It’s equivalent to repotting for a houseplant, but for a lawn.
A great way to maximize the positive impact of topdressing is to pair topdressing with organic fertilizer. Spraying fermented tea on your lawn immediately after topdressing will give it a real boost!
Precautions when you topdress a lawn
Young lawns and topdressing
Don’t topdress a lawn you recently planted or renovated. It would upset fragile root systems. Wait for at least three years. Of course, best is to have included nutrient-rich materials when preparing a new lawn.
Smothering lawn with topdress
The most important with topdressing is to not put too much!
- Topdress with recommended quantity.
- Better to topdress twice with half the amount than once with a larger quantity.
- Even at the heart of the growing season, don’t topdress more than once every three weeks.
- When leveling out holes, be especially wary of putting too much topdressing. This will backfire and kill off the grass, creating a bare patch.
- Watch out for clumps and break them up. Each clump will create a hole in the lawn. Use very dry topdressing mix for best results.
Wrong amendments added to lawn
In some cases, the topdressing mix won’t merge well with the existing lawn soil, resulting in layers. This is because contents are too different from the original soil.
- The first time you topdress, use 50% original garden soil and 50% new topdressing mix. Dig it out from a growing bed or flower bed.
- It’s also possible to analyze your soil and select or prepare the perfect topdressing mix.
- Check that the pH of the topdressing mix doesn’t stray to far away from the pH of the original soil (at most 1 point difference).
Layers shouldn’t happen because they would result in smothered grass, moss growing, and thatch forming.
Gravel or grit in the topdressing
Another type of mistake with topdressing is when it contains gravel or grit that is too large.
- Sieve the topdressing mix first.
- Best sieve grade is ¼th inch (0.5 to 0.75 cm)
Weeds sprouting everywhere after topdressing
This is possibly because the topdressing mix used had seeds in it! It often happens very often with compost, a bit less with forest soil.
- use sterilized topdressing mix, or sterilize your compost (must have reached 140°F / 60°C during the composting process).
- resume mowing about 4-5 days after having spread the topsoil. Most weeds won’t survive when cut short.
- manual weeding may be necessary to remove low-lying weeds like dandelion and clover.
Learn more about topdressing lawns
It was pioneered and developed especially for the golfing industry, where lush, pristine greens were needed for playing. In early days, it was actually the only option to grow healthy lawns since chemical fertilizers didn’t exist.
Smart tip about lawn topdress
Don’t splurge to buy equipment right immediately. Practice by hand on a small area first to get a feel of how it should go.
Then, ask around your neighborhood, someone almost certainly has the equipment for rent or for borrowing. Since it’s only needed every three years or so, it often isn’t worth purchasing at all.
Credits for images shared to Nature & Garden (all edits by Gaspard Lorthiois):
Topdressing on lawn, manual by Rosalyn & Gaspard Lorthiois, own work
Push-pull manual topdresser by Lloyd Jensen ★ under © CC BY-NC-ND 2.0
Yellow spot on lawn by Rosalyn & Gaspard Lorthiois, own work
Topdressed yellow lawn spot by Rosalyn & Gaspard Lorthiois, own work
Rake topdress lawn by Rosalyn & Gaspard Lorthiois, own work
Compost trail by Lloyd Jensen ★ under © CC BY-NC-ND 2.0