How to scarify a lawn: and when for an expert finish
Grass looking a little under the weather? Learning how and when to scarify a lawn will support healthy growth by removing nutrient-robbing moss and weeds.
Scarifying can be an important step in maintaining a beautiful lawn and refreshing a tired looking patch. Removing lawn thatch, moss and deeper deposits is more intensive than scarifying a lawn. This helps you aerate a lawn and when you fertilize a lawn you will find that it gives better results as the fertilizer reaches the roots of the grass and not just sits dormant on a layer of straw for example.
“Thatch is mostly dead grass roots and stolons, and while some thatch on your lawn can be a good thing, too much of it creates a barrier,” explains Carlos Real, lawn expert and CEO of Total Lawn (opens in new tab).
“As this barrier thickens, it restricts the amount of water, air, and nutrients that can pass through, causing your weed to suffocate and eventually die.”
How to scarify a lawn.
How to scarify a lawn
You can use a professional machine – the Sun Joe AJ805E is Amazon’s top rated purchase (opens in new tab) – or a good old-fashioned rake to scarify a lawn. ORIENTOOLS Garden Rake is Amazon’s Choice (opens in new tab)and has a useful, adjustable handle.
“Whether you use a rake or a machine is entirely up to you,” says Total Lawn’s Carlos Real. “If you are working with a small garden, a rake will do. But if you have a larger lawn, it would be more beneficial to use a professional machine as it can be quite a tiring job.”
1. Mow your lawn before scarifying
“Before you start scarifying, you should mow your lawn to about an inch and collect clippings,” says Carlos. “This can take multiple mowings as you shouldn’t cut more than a third of the grass on each mowing or you risk putting too much stress on your grass.”
2. Scarify a lawn with a rake
“Pick up and down your lawn and gently pull out any moss or thatch with your rake – try not to use too much force as some thatch will be left behind to protect your lawn,” explains Carlos. ‘Dispose of scrap.’
“Now that you’ve removed the top layer, switch directions and apply a little more pressure by pushing your rake into the ground. The reason you have to switch directions is so you’re catching any debris that got pushed back into the ground the first time.’
3. Scarify a lawn with an electric scarifier
Carlos says, “Once you’ve mowed your lawn, you should start the lawn scarifier at a high level and walk the area a few times.
“Like a rake, you should repeat the process in different directions, but each time reducing the settings so it’s less powerful (and less distant).”
When should you scarify a lawn?
How often you need to scarify depends on numerous factors including the type of soil/grass you have, the weather conditions in your area and how well you take care of your lawn. Most lawns only need thatching once or twice a year.
“Mild weather conditions are the perfect time to scarify your lawn so your lawn isn’t too hot/dry or cold/damp – so spring and fall work best,” explains Total Lawn’s Carlos Real. “Your toughest scarifying season is the fall (usually September) because heavy raking can expose the soil so you want to avoid the summer weeds.
“Light scarifying, on the other hand, should be done in the spring (around April) when it gets warmer and your lawn will recover much faster (without suffering the summer heat and drought that often slows grass growth).”
In what month should I scarify my lawn?
Heavy scarifying should be done in September and light scarifying in April.
When should you mow your lawn after scarifying?
Once your lawn has been thatched you will need to help it recover by killing any remaining moss and adding lawn grass seed and fertilizer to thicken it.
Carlos comments, “Only when your lawn is about 2 to 3 inches tall should you mow it, clipping about 1 inch each time you mow it, because once you have a healthy lawn you don’t want to ruin it by mowing it too.” subject to a lot of stress.’
Why scarify a lawn?
Scarifying your lawn has several benefits, most notably:
- It allows air, water and nutrients to enter the soil and promotes growth.
- It helps remove moss and weeds (which, when festered, deprive your healthy grass of all the nutrients it needs to survive).
- It refreshes tired looking lawns.
- It reduces the chance of moss developing in the future.
- It helps reduce soil compaction.