How to Bring Back an Overgrown Lawn, One Cut at a Time

To bring back an overgrown lawn, don't cut it all down at once. Set the mower as high as it goes. Take off no more than a third of the grass on each pass. Wait for dry grass, bag the heavy clumps, and lower the deck a notch every few days. In two or three cuts, you'll be back at a healthy height of 6 to 8 cm (2.5 to 3 inches).

Why not just cut an overgrown lawn short in one go?

It's tempting. You drop the deck, make one pass and you're done. But grass doesn't like losing most of its blade at once.

Ohio State University Extension says never to remove more than a third of the blade at a time. Going past that risks scalping. Scalping can badly damage or even kill grass, most of all in summer heat and dry spells.

A scalped lawn looks brown and patchy for weeks. Bare spots open up. That's the opposite of what you wanted from the cut.

What if I already cut it all at once?

Don't panic. Utah State University Extension says most of us have cut an overgrown lawn down in one go, and it came back. Their advice is simple: just don't make a habit of it.

So if it's done, let it be. Water it if it's dry, keep off it for a bit, and get back on a steady schedule.

How do you mow tall grass without wrecking it?

Utah State's advice for a very long lawn is to lower the height slowly over several mowings. Here's how that looks in a real yard.

1. Walk the yard first. Tall grass hides toys, hoses, sticks, stones and dog bones. A mower blade can throw them hard. Pick them up before you start.
2. Wait for dry grass. Mow in the afternoon, after the dew burns off, and not right after rain.
3. Raise the deck to its top setting. Your first pass should only take the top third off.
4. Go slow. Thick, tall grass loads up the deck. A slower walk gives the blade time to cut clean.
5. Bag or rake the clumps. Don't leave heavy piles of clippings sitting on the grass.
6. Wait a few days, then drop one notch. Mow again and take off another third.
7. Repeat until you reach your normal height. Then stay there with regular cuts.

What does "one third at a time" look like in numbers?

Say your grass is 15 cm (6 inches) tall. Here's a simple step-down plan:

Cut	Start height	Cut to
First cut	15 cm (6 in)	10 cm (4 in)
Second cut, a few days later	about 10 cm (4 in)	about 7 cm (2.75 in)
After that	regular cuts	6 to 8 cm (2.5 to 3 in)

That last line is Health Canada's height for a home lawn. Grass cut at 6 to 8 cm grows deep roots and fills in thicker. Our mowing height guide covers grass types and mower settings in more detail.

If your grass is a lot taller than 15 cm, you'll just need more steps. The rule stays the same: one third per cut.

Should you bag the clippings from an overgrown lawn?

Usually, no. On a lawn that gets mowed often, clippings should stay put. They break down fast and feed the soil. Our post on leaving clippings on the lawn explains why.

An overgrown lawn is the exception. NDSU Extension says very tall grass can gather in clumps when you cut it. Those clumps can smother the grass below. In that case, NDSU says it's wise to collect them.

So for the first cut or two, use the bagger, or rake up the piles after. Once you're back to regular cuts, you can go back to leaving the clippings.

How do you break up clumps you missed?

The City of Hamilton has a handy tip. Wet grass or cutting too much at once causes clumping. If you get a few clumps, mow that spot again from a different direction. The second pass chops them up and spreads them out.

Why does wet grass make an overgrown lawn worse?

Tall grass holds a lot of water. After rain or heavy dew, it's heavy and it lies over.

Ohio State says wet grass is harder to cut cleanly and clogs rotary mowers. NDSU adds that dry grass clumps less and mulches finer. With tall grass, both problems get bigger. You get a ragged cut, a choked deck and wet piles all over the yard.

If the forecast is a wet week, wait for a dry afternoon. Our post on mowing wet grass has more on when to hold off.

Does a sharp blade matter for tall grass?

Yes, more than usual. Ohio State says a sharp blade gives a clean cut. Dull blades fray the tips and leave brown patches.

Tall, thick grass is hard on a dull blade. The tips tear instead of slicing. A day or two later, the whole lawn has a tan, chewed look. If your blade hasn't been sharpened this season, do it before the first cut. Here's more on sharp mower blades.

What about the edges, fences and weeds?

An overgrown lawn rarely stops at the lawn. Grass creeps over walks, climbs fence lines and wraps around posts. A mower can't reach those spots.

That's a job for a string trimmer. Trim the tall stuff along fences, beds and the house after the first mow. Then edge the walks and driveway so the lines are clean again. Our trimming and edging page shows what a crew covers.

Weeds often move in when a lawn gets long. Our partner crews don't spray, and we don't give weed killer advice. Regular mowing at a good height is the part we can help with.

Can you fix an overgrown lawn in the fall?

Yes, and October is a good time to do it. Grass is still growing in early fall, so it can handle a step-down plan.

Don't leave it long for winter, though. The University of Saskatchewan says lawns left long and matted over winter are more likely to get snow mould. Their advice is to cut and rake before snow arrives.

So start the step-down cuts now, not in November. That gives you time for two or three cuts before the grass stops growing. Our post on the last mow of the season covers how to finish the year.

Could an overgrown lawn get me a by-law notice?

It can. Many Canadian cities set a maximum grass height for yards. The rules and heights change from city to city. Our guide to long grass by-laws in Canada explains how they work.

How do you stop it from getting overgrown again?

A lawn gets overgrown when cuts get skipped. A trip, a busy month or a wet stretch is all it takes. In spring, grass can grow fast. NDSU says you may need to mow every 5 days in spring.

The fix is a steady schedule. Weekly cuts in spring keep each cut under that one third mark. Our FAQ on how often to mow in Canada breaks down the timing by season.

If you're going away, line someone up before you leave. Two missed weeks in May can mean a lawn that's twice as tall when you get home.

Who does the work when you book through Golden Oak?

Golden Oak Lawn Care matches you with a vetted, insured local crew. They do the work. We stand behind it with the Golden Oak Guarantee.

If your lawn is already long, tell your crew when you book lawn mowing. A careful crew will step it down over a few visits, not scalp it in one. After that, the Worry-Free Lawn Season keeps the same crew on a steady schedule, with a photo after every cut. Your first cut is free when you book the season.

Want it handled? Get your price in 60 minutes, or call 1-866-904-LAWN.

Overgrown Lawn Questions

Sources: Utah State University Extension: basic turfgrass care, Ohio State University Extension lawn mowing fact sheet, NDSU Extension: how to mow your lawn, Health Canada: maintaining a healthy lawn, City of Hamilton: yard waste, University of Saskatchewan: snow mould.