- A lawn that has grown out of hand comes back safely when you strim the top third off first and then mow it down in stages, never in one scalping pass.
- Walk the whole lawn before any machine starts, so hedgehogs, toads and grass snakes have time to leave, then wait 3 to 5 days between the strimmer and the mower.
- Rake off every cutting, finish at about 4 cm (1½ in) and the lawn goes into winter short and even, ready for a normal first cut in spring.
The Mower Chokes, the Grass Flops Over, and Nothing Looks Like a Lawn
You pushed the mower into the grass and it coughed, clogged and cut out. Summer got away from you, or you were away, and the lawn is now a flopped-over mat that the mower will not touch. The way out is slower than one heroic pass and far kinder to the grass. Walk the area first to move any wildlife on, strim the top third off, wait 3 to 5 days, then bring the mower in on its highest setting and take the lawn down in steps.
Each step has a reason. Many standard lawn mowers struggle to cut long grass, so the strimmer goes first. Each cut then takes off no more than a third of the grass, and the days between cuts give the leaves time to regrow.
Finish by raking up or boxing every cutting, and aim for about 4 cm (1½ in), the right height for autumn and winter. The lawn goes into the cold months short, even and ready for its first normal cut in spring.
Why One Big Cut Does More Harm Than the Shaggy Lawn
The urge is to hire the biggest mower you can find, set it low and be done in an hour. Resist it. The rule for any cut is to remove no more than one-third of the grass height. Cutting too much at once stresses the grass and raises the risk of weeds and disease.
The reason sits in the blades themselves. Every blade of grass is a leaf that feeds the plant. Take away more than a third and root growth can stop while the leaves and shoots regrow. A scalped lawn is a lawn whose roots go without while it rebuilds its leaves, and it leaves thin, open turf for weeds to move into. Heading into winter, the grass needs its leaves, not a fresh start.
Work it through with a lawn that has reached 15 cm (6 in). The strimmer takes it to 10 cm (4 in). Several days later, the mower takes another third off. Keep repeating that pattern until the grass reaches its finishing height. Several short sessions beat one brutal one.
That finishing height is about 4 cm (1½ in) for spring, autumn and winter, against about 2.5 cm (1 in) in summer. Resist the urge to go lower on the last pass: cutting a lawn too short before winter brings stress of its own.
Check for Wildlife, Then Strim the Top Off
Before any blade or string spins, make sure nothing is living in the grass. Hedgehogs, toads, grass snakes and more could be hiding out of sight, even in small areas. Walk through the whole lawn making lots of noise and give any animals time to get away. Hedgehogs find quiet spots to hibernate from October or November through to March or April, and strimmers are one of the biggest causes of fatal or severely injuring hedgehog accidents, so check the whole area carefully before the strimmer starts. Take the same walk to find and remove stones and other objects that could damage the mower blades.
Then kit up. The Royal Horticultural Society lists eye goggles, ear defenders, sturdy gloves and tough footwear, and adds that strimmers kick up lots of debris, so a face visor is recommended. Read the manufacturer’s safety and operating instructions before you start.
A strimmer is the easiest way to tackle a smaller area. Take off a third of the length, working across the whole patch. Strimmers chop the material quite small, which makes it harder to rake out, so keep the strimmer to this first pass and let the mower and its collection box do the rest. On a small patch a scythe is the environmentally friendly alternative, but the technique is tricky, so get expert guidance before you swing one.
Now leave it alone for 3 to 5 days. The wait is part of the method. Cutting a third off in one go and a third off again a few days later keeps every pass inside the limit that the grass can take.
Mow It Down in Stages, on Dry Grass Only
Pick a dry day. The grass should be dry so the blades cut cleanly and do not clog. Wet grass clumps and clogs the mower, rips the grass blades so the tips turn brown, and gets dropped in patches that smother the living grass and lead to brown patches. Wait until the lawn has dried out. In cold weather, never mow or walk on frosty grass, which damages it. Wait until later in the day, when the lawn has defrosted, or leave the job for another day.
Emma Sothern, a gardening and lawn expert who runs the website Garden Zoo with her husband, cautions against mowing wet grass. “No matter how scraggly your yard has gotten during rainy weeks, avoid cutting it while it’s still wet,” she says. “Cutting wet grass inhibits growth and raises the chance of soil compaction.” The full case against mowing while it is still wet is worth a read before you pick your day.
Set the deck to the highest setting for the first pass. Mow the edges first to mark the area and give you room to turn, then work up and down in straight lines, overlapping each row slightly. Walk steadily and empty the collection box often: it lets you see your progress and stops clumps dropping on the lawn.
How long to wait before the second pass depends on how long the grass was. A lawn only slightly over its limit can take its second, lower cut later that day or the next. A lawn that was properly long needs several days. Lower the deck each time so no pass removes more than a third, and repeat until the grass sits at about 4 cm (1½ in).
Keep the blade sharp for all of it. Coulter Lewis, co-founder and CEO of Sunday, a subscription direct-to-consumer lawn care company, puts it plainly. “Dull blades tear at grass, making it look frayed and messy and causing undue stress,” he says. “Torn and shredded grass from dull mower blades is more vulnerable to disease than clean-cut grass.” If your finished lawn shows ragged, torn grass tips, the blade is the first place to look.
If thistles were hiding in the long grass, dig out or pull out the plants before they set seed.
Clear the Cuttings Before They Smother the Grass
The cuttings from a long lawn must leave the lawn. Clumps left behind smother the living grass and block its sunlight, so pick up any clump you see. Long cuttings break down more slowly than short ones, cut off the light the grass needs and hold moisture against the turf, which can bring disease. Removing clippings can also help prevent some lawn fungal problems. Any cut that produces substantial clippings should be removed and composted.
The easy routine is to empty the box often and rake up whatever the box misses. Add the cuttings to your compost heap between layers of woodier material. If you have used a selective weedkiller on the lawn, follow the label on how to dispose of the clippings.
One last pass finishes the job. Mow once more around the outside to tidy up any marks left by turning the mower, and trim the edges with long-handled edging shears. Change your mowing direction at least every month, so you catch stray blades and do not wear wheel ruts into the turf. Glen DellaValle, CEO of DellaValle Management, a property management company that cares for more than 150 acres of private lawn, agrees. “Rotating the pattern in which you cut your grass will help it be more evenly cut over the long term,” he says.
How to Stop It Happening Again (and When to Call a Contractor)
A lawn that is mown weekly or fortnightly between March and October never gets far enough ahead of the mower to need rescue. Mowing is not necessary in prolonged dry spells in summer, and milder winters sometimes call for an occasional trim between late autumn and early spring. Watch the growth rate and let that decide the day, not the calendar.
Sometimes the long grass was not an accident. You can let a lawn grow by choosing not to mow in the summer months, mow for the last time in April, and leave the whole lawn or just a section uncut, with paths mown through it. The wild plants already in the grass grow up and flower, adding colour and attracting pollinating insects and other wildlife. The autumn cut then tidies the result. One or two cuts between the end of August and late November remove surplus growth and keep the grasses at bay, letting wildflowers thrive. After the last cut of the season, the area can be kept mown so the grass is short and neat through winter. If the cutting leaves substantial clippings, remove and compost them, as above.
Know when the job is beyond you. Larger areas are best tackled with a ride-on mower, a heavy-duty mower such as a sickle-bar mower or motor scythe, or a two-wheeled strimmer. These are machines most households do not own, and that is when a contractor earns the fee. If the grass is too much for a hand-held strimmer and a rake, call someone in rather than fight the mower for an afternoon.
In spring, set the mower to its highest setting for the first cut of the year. If you took the lawn down in stages this autumn, the grass underneath is short, even and healthy, and that first cut is the easy one.
