What would happen to my lawn if I just didn't rake the leaves?

October 28, 2009 4:15 PM

What would happen to my lawn if I just didn't rake the leaves?

I don't particularly care if my lawn is covered in leaves. But will it actually damage my (normal grass) lawn if I just leave them there until they blow away or disintegrate or whatever? Come Spring, will I have a barren patch of dirt where there used to be grass?

posted by Flunkie to home & garden (25 comments total)

Your lawn will die a quick death within a few seasons. The lawn of the house I grew up in shrinks every year because the leaves don't get completely removed from the borders. I remember where the trees used to be in relation to the lawn and there is about a 6' difference in most places now.
posted by 517 at 4:21 PM on October 28

I think it must depend on several factors, such as how deep the leaves fall, how windy it is where you are, etc. Because I never rake the leaves from my trees and the lawn just keeps chugging along. It takes some patches a little longer to catch up in the spring, but by midsummer you can't tell where the leaves had been.
posted by bricoleur at 4:27 PM on October 28

the leaves would block light from reaching the grass and inhibit evaporation of water.
posted by rhizome at 4:30 PM on October 28

and the leaves encourage the growth of mold and/or fungus which isn't very friendly to the grass.
posted by GuyZero at 4:32 PM on October 28

1) what kind of grass?
2) what kind of leaves?

Would you be really upset if the lawn dies, and you have to re-turf? (if not, just try it!)

What about leave mulch for your garden?
posted by titanium_geek at 4:33 PM on October 28 [1 favorite]

What would happen to my lawn if I just didn't rake the leaves?

Your neighbors would probably hate you.
posted by ASM at 4:41 PM on October 28

It will choke your grass if fairly deep and all over the place.
posted by Postroad at 4:47 PM on October 28

If you want an easy way out, just use the leaves to cover the rest of your landscaping. They make pretty awesome mulch for the winter and break down into good humus come spring. Unless they're oak or walnut leaves. Oak leaves don't break down fast enough and walnut leaves have compounds in them that poison plants.
posted by fiercekitten at 4:50 PM on October 28 [2 favorites]

I made the decision one year not to get rid of the leaves, assuming they'd just compost and would be gone by spring. Well, when the rainy season came, the leaves turned into wet, heavy, matted masses that flattened and melted into the grass. And when spring came and the weather dried up, I had dozens of wet, muddy holes in my formerly pretty lawn.

Now I rake.
posted by mudpuppie at 4:54 PM on October 28 [1 favorite]

Every year since we moved to our current home in 2005 until last year I spent the entire fall dreading collecting and disposing of the leaves which blanket my entire yard about a foot deep.

Last year, instead of taking over three days to get rid of them, I ran my mulching mower over them two times and pretty much reduced them to dust (or at least to fragments under about 1/2 inch square). It took me under three hours, including blowing them out of the flower beds and on to the grass prior to mowing.

This past spring and summer I had the best looking yard I've ever had. I have raked my last leaf.
posted by imjustsaying at 4:55 PM on October 28 [6 favorites]

Come spring, you would have a nice gooey, brown, rotting mat of leaves. They don't "blow away or disintegrate or whatever." They rot.
posted by The World Famous at 5:00 PM on October 28 [1 favorite]

I've seen some plant writers who think (like our reasonably well-respected Anchorage garden man here) that if you don't rake, it's no big deal. The one or two times I haven't, my lawn has survived with no ill effect.

However, at the moment I live in a slightly classier neighborhood and shamed by my neighbors into- not raking- but mowing (like imjustsaying) all my leaves up, which is enormously more efficient and less time-consuming. I don't have inches and inches of thick leaves, but I do have a good amount (up to 4-5 inches deep), and my trusty mower just chews 'em up and mulches them in hours and hours less time than it would take to rake and bag.
posted by charmedimsure at 5:09 PM on October 28

Question for the mulching mower folks: once you've mowed over the leaves, do you leave the remaining leaf mulch on the lawn?
posted by Majorita at 5:17 PM on October 28

For Majorita- I've done it both ways and it doesn't seem to matter either way when the grass comes up in the spring. It fills the mower bag up fairly quickly, so usually I take the lazy way out and don't bother to get it up off the ground. If we're not having a particularly rainy fall, the debris is small enough that a lot of times the bulk of it just blows away and biodegrades elsewhere.
posted by charmedimsure at 5:25 PM on October 28

Regarding mowing leaves, I did it often enough as a kid. When we didn't bag the leaves (of which we really didn't have many), I'd go back and rake where the mulch was expelled. Our mower tended to leave a line of mulch instead of spreading is nice and evenly. Otherwise, I reckon we'd end up with lines of dead grass.
posted by jmd82 at 5:58 PM on October 28

I've seen some plant writers who think (like our reasonably well-respected Anchorage garden man here) that if you don't rake, it's no big deal.

It's a different story if you have solid snow cover on your lawn for a few months. In any case, freezing and thawing of organic material in the spring releases soluble phosphates, carbohydrates, and nitrates. If you have runoff from your garden into storm drains or waterways, these nutrients can promote algae bloom. When algal blooms die off, the decomposition removes oxygen from the water, killing aquatic organisms that need oxygen. So raking and composting leaves or using a mulching mower to chop them up is preferable to leaving them entire on the lawn in any case; composting means those useful nutrients can be used by the gardener rather than washed away.
posted by oneirodynia at 5:59 PM on October 28

Actually if you live out in the country, allowing the leaves to stay keeps the grass thinned out and keeps ticks from getting established. We have both post oak and pine, whose leaves have different decomposition characteristics, and we've ended up with a sort of a mulch-like ground cover with scattered grass and loamy dirt, and it looks fairly decent and doesn't get muddy at all when it rains. I've often been tempted to rake it up and start a lawn, but then I start thinking about ticks and having to mow.
posted by crapmatic at 6:02 PM on October 28 [2 favorites]

I've always heard that ticks live in leaf litter, especially damp leaf litter. People who spend time in oak woodlands in California are advised to stay away from dead wood, logs, and leaf litter to help avoid getting Lyme disease.
posted by oneirodynia at 6:09 PM on October 28

Yeah, hadn't thought about the snow cover factor- I've only ever been a lawn-owner in Alaska...so the poster's mileage with that could probably vary pretty dramatically depending on location.

Regardless, however, the it sounds like the mulching thing should still be okay and it is So. Much. Easier.
posted by charmedimsure at 6:20 PM on October 28

We usually leave a light coating of leaves down but get rid of the biggest piles. Ours is the earliest on our street to green up in the spring, with no fertilizer. The lawn is actually so healthy it's annoying. I'm growing St. Augustine in part sun/ light shade on the Gulf Coast.

The easiest way we have to get up the big piles of leaves is to put the bag on the lawn mower, vacuum them up, and dump the chopped up leaves into the compost bin.
posted by zinfandel at 8:30 PM on October 28

Most northern lawn grasses are so-called "cool-season", which means that during the fall and even winter, they grow. During the height of summer, when if you don't water the grass goes brown, it's hibernating (of course, it can die in these conditions too, but generally all you need is a rainfall to bring it back to green life). So if you leave your leaves, you are actually cutting off the sunlight from the grass, inhibiting some of its most productive growth months. Typically the winter is a time of deepening roots rather than extending grass leaves (blades), so you're actually weakening its future ability to bounce back from summer droughts and what have you.

If you really want to do it right, mulch up your leaves, and add them to your compost with your last green-grass mow. Then in the spring, use the compost as a top dressing.
posted by dhartung at 8:55 PM on October 28

if you leave them on the lawn they will become stuck together and frozen and they will be like thousands of slick banana peels for your guests and the mailman who walk across your lawn. So I would go over them with the lawn mower. Or make a clear path for guests. Or get an umbrella insurance policy.
posted by cda at 9:22 PM on October 28

Wow, really? I guess I never realized how good I have it. I live in the Pacific Northwest, where the half life of a fallen leaf is about two months.

I've never raked a single leaf. Some time mid-winter they all just sort of dissolve. I live way out in the boonies, so I don't have neighbors' opinions to worry about. The lawn does just fine.
posted by ErikaB at 10:05 PM on October 28

it depends a bit on what kind of trees you have also. I have many oak trees and those leaves just do NOT decompose quickly. so, if I leave mine, it is, as others stated, a wet, slippery, stinky brown mat of leaves the next spring that choke out and kill the grass. I rake mine into the woods behind my house, as even mowing them over often will not break them up.
posted by midwestguy at 7:23 AM on October 29

Question for the mulching mower folks: once you've mowed over the leaves, do you leave the remaining leaf mulch on the lawn?

A recent study, cited by my local Cornell Cooperative Extension agent, reported that Oak and Maple leaves, when mowed into a lawn, suppress weed seed from germinating, especially crab grass. So if you already mow, why not mow the leaves? Use a mulching blade and keep it sharp.
posted by recurve at 2:10 AM on November 1