How-to
Grasscycling: Why Leaving Grass Clippings on Your Lawn Helps
IllustrationYes, leave the clippings on your lawn. That's called grasscycling. Cities like Hamilton, Red Deer and Kamloops all ask people to do it. Clippings feed the soil, hold in moisture and usually vanish within three days. Kamloops says they can give about one third of your lawn's nutrient needs. They don't cause thatch. The trick is to mow often, mow dry and keep the blade sharp.
What is grasscycling?
Grasscycling is a fancy name for a lazy habit. You take the bag off the mower. You mow. You leave the clippings where they fall.
The City of Red Deer puts it simply. Grasscycling is "as simple as removing the collection bag off your lawn mower." You don't need a special mower to do it.
The short bits of grass drop down between the blades. They dry, break down and go back into the soil. Hamilton says most people find the clippings are gone within three days. St. Albert says the same thing, and gives the reason: clippings are full of water, so they break down fast.
Why leave grass clippings on the lawn?
Canadian cities push grasscycling for a few plain reasons. Here's what their own pages say:
- It feeds the lawn. Kamloops says mulched clippings can give about one third of your lawn's nutrient needs.
- It holds moisture. London and Red Deer both say clippings help the soil keep water.
- It feeds worms. Hamilton says clippings are food for worms, and worms loosen your soil for free.
- It saves your back. Red Deer lists no raking, no lifting and no carrying heavy bags.
- It keeps the green bin free. St. Albert says grass can fill up to 75 per cent of a green cart in summer.
Some cities go further. London has no curbside pickup for grass clippings at all. Hamilton still takes grass with leaf and yard waste, but it asks people to leave clippings on the lawn first.
Do grass clippings cause thatch?
No. This is the most common worry, and the cities are clear on it.
Hamilton says grasscycling does not cause thatch. Thatch is a tight layer of stems and roots between the green grass and the soil. Red Deer agrees. It says thatch is mostly grass roots, not clippings. It points to watering too often as the cause.
Clippings are soft and wet. They break down in days. Thatch is made of the tough parts of the plant that rot slowly. They're two different things.
Will clippings make my lawn look messy?
Not if the lawn is cut the right way. Hamilton says clippings can't be seen when a lawn is cut properly. Red Deer says they settle into the soil and the lawn looks healthier for it.
Messy clippings come from a few habits:
- Mowing wet grass. Wet clippings stick together in clumps.
- Letting the grass get too long. Red Deer says longer clippings sit on top of the grass instead of settling in.
- Taking too much off at once. Hamilton says that causes clumps too.
- Mowing with a dull blade. Red Deer says dull blades tear grass instead of cutting it.
Fix those four things and the clippings disappear from sight. Hamilton also says clippings don't turn the grass brown. They add nutrients back to the soil.
How do you grasscycle the right way?
Here are the steps the cities agree on.
Follow the one-third rule
Red Deer says to mow often enough that you never cut more than one third of the height. Hamilton adds a cap: no more than 2.5 cm (1 inch) at any one time. Kamloops gives an easy example. If your grass is 9 cm (about 3.5 inches), take off 3 cm and leave 6 cm.
Keep the blade high
Hamilton says to keep the mower at about 6 to 7.5 cm (2.5 to 3 inches). Our post on why sharp mower blades matter covers the blade side of a clean cut.
Mow often
Red Deer says every 5 to 7 days. St. Albert says every 4 to 5 days in the main growing season, and about once a week in the shoulder season. Our guide to how often to mow in Canada walks through the rhythm by month.
Mow when it's dry
Wait for the dew to burn off. Skip the hour after rain. Dry clippings scatter. Wet ones clump.
Clean up the hard surfaces
Red Deer asks you to sweep clippings off the driveway and back onto the lawn, away from the storm drain. A quick blow or sweep after each cut takes care of it.
What if the grass already got too long?
It happens. You go away for a week, it rains, and the lawn shoots up. Don't scalp it in one pass.
Hamilton says to cut off a little, lower the blade, then cut off a little more. St. Albert suggests a double cut, with the second pass at a right angle to the first. That chops the long clippings smaller so they can drop in.
If you still see clumps, Hamilton says to mow that spot again from a different direction. That breaks them up. On a very long lawn, it's fine to bag that one cut. Then get back on a regular schedule.
Do you need a mulching mower to grasscycle?
No. Red Deer says a mulching mower is a nice option, but you don't need one. If you cut high and your blade is sharp, any mower works. A mulching blade just chops the clippings smaller so they spread out more evenly.
If your mower only has a bag or a side chute, take the bag off and mow. Point the chute toward the lawn, not toward beds, walks or the street.
Does grasscycling spread lawn disease?
Hamilton says it doesn't. Watering, fertilizing and blade sharpness affect lawn disease more than clippings do. Red Deer says the same. Our partner crews don't spray, and Golden Oak gives no disease treatment advice.
What about grasscycling in the fall?
Grass slows down in fall. Hamilton says late summer and fall cuts can drop to about once a week. Grasscycling still works fine until your last mow.
The bigger fall job is leaves. A thin layer of leaves can be shredded with the mower along with the grass. A thick layer needs to come off. Our post on mulching leaves with a lawn mower explains where the line is. A fall cleanup handles the rest before snow.
Should your lawn crew leave the clippings?
For a regular cut, usually yes. The City of Brantford even says to tell your lawn service to use the grasscycling method.
Ask your crew how they handle clippings before the season starts. A good crew mows often enough that clippings drop out of sight. It blows clippings off the drive, walk and patio after every cut. If you'd rather have the clippings bagged and hauled away, say so up front. Haul-away adds time, so it can change your price.
Golden Oak Lawn Care matches you with a vetted, insured local partner crew. They do the work. We stand behind it with the Golden Oak Guarantee.
Your crew mows your lawn on a set schedule and texts you a photo after every cut. If you see clumps or a messy finish, text us a photo within 24 hours. Your crew re-cuts it free within 48 hours. The Worry-Free Lawn Season plan books the season up front, and the first cut is free. We price every lawn by its size from satellite images, so no one needs to visit.
Want it handled? Get your price in 60 minutes, or call 1-866-904-LAWN.
Grasscycling Questions
Is it better to bag grass clippings or leave them?
Leave them on most cuts. Hamilton, Red Deer, St. Albert and Kamloops all ask residents to grasscycle. Clippings feed the soil and help hold moisture. Bag only when the grass got too long and clumps won't break up.
How long do grass clippings take to break down?
About three days. Hamilton says most people find their clippings gone within three days of mowing. St. Albert says they break down fast because they're full of water.
Do grass clippings cause thatch?
No. Hamilton says thatch is a layer of stems and roots, not clippings. Red Deer says thatch is mostly roots and points to watering too often as the cause.
Can I grasscycle with a regular mower?
Yes. Red Deer says you don't need a mulching mower. Cut high, keep the blade sharp and mow often. Any mower will do the job.
Sources: City of Red Deer grasscycling, City of Hamilton yard waste and grasscycling, City of Kamloops healthy lawns, City of St. Albert grasscycling, City of London yard waste, City of Brantford yard waste.
