Scarifying the lawn correctly - why, when and how?

Scarifying the lawn correctly - why, when and how?

Why is scarifying useful?

If moss, weeds and rotten clippings gain the upper hand in the lawn, young grasses can no longer penetrate the felt. When scarifying, the sward is scored a few millimeters deep. Rotating knives comb out the green area. The green rubbish remains on the lawn surface and is simply swept away. As a result, the roots of the grass can breathe deeply again and process nutrients better.

Scarifying the lawn - questioning is allowed

The passionate pleadings of lawn experts suggest that it is necessary to scarify a lawn every year. Before you devote yourself to the time-consuming and energy-consuming procedure, you should critically question the relationship between effort and success. So that you can make a clear decision without a lot of headache, we have put together the following criteria for yes or no:

thick moss cushionslittle to no moss
plenty of weedsisolated weed growth
bald spots from thatchdense sward with no gaps

Don't you want to rely on purely visual factors before you decide between yes or no? Then pick up a garden rake or a cultivator. Loosely rake the lawn in question at various points. If moss, weeds and old clippings get stuck in the tines, you should scarify your lawn.

When is the best season?

Basically, you can scarify your lawn throughout the growing season. The thermometer announces when the starting shot is fired. The temperatures should not drop below 10 degrees Celsius even at night. This requirement also applies if you want to determine by when you can comb out a green area in autumn.

The best time of year to scarify a lawn is in the spring during the months of March and April. In wine-growing regions with mild winter, the time window can open as early as February. If you want to leave your lawn freshly combed in the winter, scarify it a second time in September or October. Once again, gardeners in mild locations enjoy the privilege of being able to scarify a lawn until November.

How often does scarifying make sense?

You should scarify a moss-covered lawn with dense weeds at least once a year. So that you can enjoy the velvet green lawn carpet for a long time, spring is the best date. A heavily used sports and play lawn benefits from combing out the green area a second time in autumn. Without the stress of moss, weeds and cuttings left behind, ornamental and shadow lawns are of course better equipped for winter.

Exclusion criteria at a glance

After prolonged rain, your lawn is so softened that scarifying can have fatal consequences. Scarifying a lawn in winter is also doomed to failure. The following overview summarizes the conditions under which you have to reckon with significant problems:

Exclusion criterionDamage
wet lawndestroyed lawn
damp lawnnoble grasses plucked in places
frozen lawnno scarifying effect
young lawncombed out seedlings and young grasses

If you enjoy the colorful flowers in the midst of the lawn, you should carefully consider whether you are combing out moss and weeds or not. Scarifying a lawn despite flowers destroys the colorful splashes of color for a long time. Scarifiers (€ 76.01 at Amazon *) pull everything out of the ground that they can get hold of. Flower roots are not spared from the rotating knives.


As a messed up rag rug, a lawn confronts the gardener with the decision: mill or scarify? You should not underestimate the regenerative capacity of noble grasses. Before you peel off a lawn and create a new one, it is worth doing a test with the scarifier. Previous fertilization vitalizes the last lawn grass. After two to three weeks, comb out the green area, sprinkle overseed and inspect the result after a few weeks.

Scarifying can be done manually and by machine

It is your horticultural decision whether to scarify a lawn by hand or with a machine. A hand tool works with rigid steel knives that are mounted along an axis between two wheels. Pulling the hand scarifier through the sward while applying pressure removes moss and weeds. There is no doubt that manual scarifying requires considerable effort and is primarily useful for small lawns.

Motorized scarifiers work with rotating knife rollers that cut the ground and pull out thatch. The working depth can be adjusted individually. The devices are available from specialist retailers either as electric or petrol scarifiers.

Bargain hunters rent machines and aids

With a well-tended lawn, scarifying is not on the schedule every year. Investing in expensive machines and tools is not worthwhile for many hobby gardeners. Clever bargain hunters fall back on the offers of various hardware stores and some private providers to rent electric, gasoline and hand scarifiers at a reasonable price for one day.

Observe the correct order

The key to success is the correct sequence of work steps. The following list gives an overview of the sequence in which to scarify your lawn correctly:

  • 2-3 weeks in advance: Mow the lawn to a height of 4 cm and fertilize
  • On the chosen date: mow the lawn to 2-3 cm stalk height, scarify and sweep
  • After scarifying: sand and / or lime if necessary, water regularly
  • 7 to 10 days after scarifying: re-sow and blast any visible bald spots
  • 3-4 weeks after scarifying: mow for the first time and fertilize again

So that a scarified lawn turns into an even, representative green area, please be patient after scarifying. Allow the sand, lime and overseed to take effect before you mow. The stalks should be at least 8 centimeters high.

Mow or scarify first?

A look at this tried and tested sequence in the work flow clears a classic stumbling block for the perfectly scarified lawn. Hobby gardeners with little experience ask themselves whether they should mow or scarify first. So that the rotating blades of the scarifier or the tines of the rake pinpoint the lawn thatch at the roots, previous mowing clears the way to the annoying moss and brazen weeds.

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When you've raged in the garden for four hours and your experience afterwards is a bit sobering. # garden # gardening # summer # green thumb # lawn # hedge # scarify

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Step-by-step instructions - how to scarify in an exemplary manner

In order to properly scarify a large lawn from around 200 square meters, please plan a working day. How to proceed professionally step by step:

  • Mow the lawn to 2 to 3 cm
  • Adjust the scarifier to the required working depth
  • Position the device parallel to the edge of the lawn and start it up
  • Scarify the lawn lengthways slowly and without stopping
  • Sweep away clippings with a rake
  • Comb out and sweep the green area crosswise
  • If necessary, sand and lime the lawn
  • Finally, irrigate the scarified lawn

Home gardeners are worried about how deep a lawn should be scarified. Years of practice in the private and commercial sector have shown that a combing depth of 3 millimeters is recommended. Set the scarifier accordingly and walk a few meters across the lawn. If there is a thick layer of moss, felt and weeds on the web, no further adjustments are required.


Humus levels holes in the lawn

If lawnmowers and scarifiers bump over the green area, level out the bumps with humus. The best opportunity for the remedial measure is after the moss and weeds have been combed out. Enrich the humus to a third with fine-grain sand. You distribute this mix evenly over all gaps in the lawn. Then roll the damaged areas smooth and scatter lawn seeds. Sieve the light germs thinly with sand and pour with a fine shower. The use of peat in the near-natural home garden has long been frowned upon for this purpose in order to stop the overexploitation of our valuable moorland.

Sow the lawn after scarifying - this is how it works

Are bald spots in the lawn a thorn in your side and wondering when to re-sow? Lawn seeds find excellent framework conditions for rapid germination in the scarified lawn. Scarifying removes moss, weeds and felt that make life difficult for young lawn seeds. How to properly sow the lawn after scarifying:

  • The best time after scarifying is between April and September
  • Pour seeds into a spreader
  • Set the dosage according to the manufacturer's instructions
  • Scatter lawn seeds lengthways and crossways
  • Work in easily with a rake and sprinkle

For the next four weeks, keep the lawn area that has been scarified and re-sown slightly moist. In summer drought you should sprinkle daily. From a stalk height of around 8 centimeters, mow the rehabilitated lawn to 4 to 5 centimeters.


Grass reseeding without scarifying is usually doomed to failure. An all-suffocating layer forms on the sward of moss, weeds and leftover clippings. In order for lawn seeds to germinate and seedlings to take root, the felty bulwark must first give way.

Sanding the lawn after scarifying - when and how?

If a lawn thrives on clay soil, the risk of waterlogging hovers like a sword of Damocles over the green area after every heavy downpour. By applying fine-grain sand after scarifying, you loosen up compacted subsoil and create effective drainage. Sand with a grain size of 0 to 2 mm, such as washed Rhine sand or play sand, is well suited. Spread the sand with a spreader that you set to a dosage of 5 liters per square meter.

Aerate or scarify the lawn? - Differences

Scarifying scratches the surface of the sward to remove weeds, moss cushions and old lawn clippings. If the lawn remains sparse, a more in-depth treatment will solve the problem. By aerating a lawn, you break up compaction down to a depth of 10 centimeters. In technical jargon, the freshness cure is called aeration.

Motorized coring machines work with hollow spoons that deeply perforate the oxygen-poor lawn. Machine rental companies offer the devices at low rental prices. You can ventilate smaller lawns manually. Hand fans are made of hollow soil nails on a rail. These are pressed into the sward using a handle with a handle and the cones of soil are caught in a tub. Then sweep fine-grain sand into the punched lawn holes as drainage.


Liming only when necessary

Liming does not automatically count towards the professional post-treatment of a combed lawn. Increased moss growth signals that the pH value is too low and should be improved with the help of lime. If, on the other hand, clover and other weeds mixed under the thatch, you should check the actual pH value. A soil test, which you can purchase at a reasonable price in garden centers and hardware stores, removes any last doubts. A pH value below 5.5 signals that you should lime your lawn after scarifying.

frequently asked Questions

When can we scarify our newly created lawn for the first time?

New lawn is so well rooted that you can scarify the green area after two to three years at the earliest. A scarifier cannot distinguish between moss, weeds and noble grass. Before scarifying for the first time, please wait until the delicate stalks have taken root so deep that they do not give in to a slight pull.

I would like to scarify, re-sow and maintain my lawn according to the lunar calendar. What should I pay particular attention to?

From our point of view it does not make sense to maintain a lawn exclusively according to the lunar calendar. Rather, a combination of local framework conditions and appointments according to the lunar calendar has proven itself in daily gardening practice. When the lunar calendar recommends an appointment for scarifying, the lawn should be dry and the soil should be thawed.

Demoss your lawn without scarifying it - is that possible?

Removing moss from your lawn without scarifying is not an easy task. The aim is to deprive the moss of the basis of life in the lawn by improving the framework conditions for the noble grasses. The main causes of a moss-covered lawn are: too low a pH value, lack of nutrients, soil compaction, waterlogging and mowing that is too deep.

Why should I fertilize my lawn first and then scarify it? Isn't that a waste of expensive lawn manure?

Valuable lawn grass has to be tough so that it does not fall victim to the rotating blades of the scarifier. You significantly increase the resistance of the stalks if you fertilize a lawn first and then scarify it after about two weeks. As a further advantage, small gaps in the combed out lawn close faster if you have applied lawn fertilizer beforehand.

Should I scarify the lawn in the fall?

During the summer, mowing and plant residues collect between the noble grasses. In this way the lawn becomes matted and the soil compacts. If moss and weeds also sprout, water, nutrients and air can no longer get to the roots of the lawn. It is therefore advisable to scarify the meadow again before winter. How to do it right:

  • Scarify the matted meadow once lengthways in August or September
  • The knives do not cut deeper than 3 millimeters into the sward
  • After a week fertilize the lawn and water repeatedly

At this time of year the lawn in the garden needs a different nutrient composition than in spring. Instead of nitrogen and phosphorus, the focus is now on potassium. This mineral strengthens the plant cells against the stresses of winter. Thanks to potassium, the cell walls are particularly resistant to the fluctuating temperatures between frost and thaw. Experienced lawn whisperers therefore fertilize every year as part of autumn care with Patentkali after scarifying.

What alternatives are there to scarifying?

Experienced gardeners scarify their lawn at least once a year if necessary. However, those who do not want to have a sparse lawn in front of their eyes for several weeks will encounter the problem with continuity. Instead of cutting into the sod with knives once, the lawn is aired after each mowing. How to do it right:

  • The lawn has not mutated into a completely moss-covered meadow
  • A stable, high-quality spring broom is available
  • After each mowing, clean the grass area thoroughly with the spring brush
  • Moss and cuttings that have not been caught are continuously removed

If all other measures of professional lawn care are carried out in the garden, you can save yourself scarifying every year thanks to this persistence. Since you will encounter each weed individually during this activity, you can simply prick out unwanted guests such as dandelions and the like with the weed picker.


Anyone who is willing to spend a little money can have their lawn scarified by a specialist. The decisive factor for calculating the costs is the size of the green area. Experienced specialists do all scarifying work, including any preparatory work and rework, for as little as 1.19 euros per square meter. If you choose a local provider, there are no separate travel costs.