Love ‘Em and Leave ‘Em
October 23rd, 2012
One of the many perplexities of humans that I haven’t figured out yet is why we spend so much time in fall trying to get rid of every last leaf in the yard, then turn around in spring and pay for products such as fertilizer, mulch and soil amendments.
Leaves are all of those things. They’re an excellent and free resource that drops from the sky – nothing short of a gardening gift from God.
They’re not nature’s trash, and I think it’s time we rethink our leafy habits.
I see a lot of yardeners this time of year using noise-polluting, air-polluting, gas-powered leaf blowers to move their leaves to the curb. The American Lung Association will tell you that’s a huge source of allergens – not only fine particulates but molds, toxins, bird poop, etc. stirred up from the ground.
Then we add to our blower, gas and antihistamine bill by paying even more money for our municipalities to come around in gas-eating trucks to suck up the leaves and haul them away.
When the wind blows before the truck comes, the leaves blow over the street, where they become a driving hazard in wet weather.
Then there’s leaf-caused car fires. I remember the late Camp Hill Borough Manager Andy Janssen telling me about the many fires that happen every fall when people park over curbside leaf piles and set the dry leaves on fire with their hot engines.
Even when the piles stay in place, rain leaches nutrients from the leaves and carries this brew into the storm-sewer system, where it ultimately adds to nitrogen and phosphorus excesses in the Cheasapeake Bay.
Curbside leaves are also notorious for clogging storm sewers.
On the other hand, leaves make a wonderful natural blanket to insulate our gardens over winter (i.e. free mulch).
They’re an ideal ingredient in the compost pile when mixed with year-end grass clips and frost-killed plants (i.e. free soil).
Instead of polluting water with leached nutrition, leaf nutrition is much better redirected onto our lawns and gardens (i.e. free fertilizer).
And when worked into soil, leaves are one of the best materials to break up our lousy clay and shale (i.e. free soil amendment).
Rather than blow my leaves away, I gather them or use them in place. Most years, I’ll even go out to my curb to retrieve leaves that have fallen there.
Leaves that fall and/or blow into my shrub and perennial beds or around trees, I “leave” in place. Come spring, they’ve packed down and already are decaying, making an effective mulch that also feeds the soil.
If you don’t like the look of that, just top it with a light layer of bark mulch for that “clean” look that’s so popular. No need to rake the leaves off first.
In the lawn, I mow over my leaves. Chopped into bits, those leaves work their way into the lawn soil by spring, where they again add organic matter and nutrition to feed the grass. These don’t cause thatch as many people think.
Michigan State University researchers did some comparisons of lawns where leaves were mowed in vs. raked off, and the leaves-on lawns were healthier and better performing. Between mowing in leaves and letting your grass clips lie, it’s a no-brainer. You’re returning nutrition and organic matter to the lawn instead of draining it with constant “nutrition withdrawals.” That makes a whole lot more sense to me than draining the lawn account and then paying to fertilize four or five or six times a year to compensate.
If you like the lawn neat, just run over the leaves twice to double-chop them.
If you have a ton of trees that all drop at once and there are so many leaves that you can’t even see the lawn, then it’s best to get them off.
Two other instances where you might consider moving leaves – ones that are blowing up in piles against buildings and ones thickly covering evergreen groundcovers, such as pachysandra and vinca.
Personally, I use a people-powered rake in these cases. I can use the exercise (i.e. free health club). A decent alternative is an electric or battery-powered leaf vacuum that sucks up the leaves and chops them before depositing them in an attached bag. That still stirs up some allergens, but at least you’re not directly using gas or blowing the leaves to the curb.
Whether raking or bagging, don’t toss the leaves.
I always keep a few bags to use as mulch in the vegetable garden the following spring. It’s a free alternative to straw – and no hay-seed or weed germination to worry about.
I also use a few bags as insulation around my marginally hardy fig tree. I wrap a tarp around the tree and stuff the insides with leaves, then tie off the top for winter.
I’ll also move some of the excess leaves from the lawn or groundcover to places where they’re more needed, such as around trees, shrubs and perennials.
In years where I’m digging a new bed or improving an existing one, I’ll dig in some of the leaves to improve drainage. They’ll compost quickly in the soil.
And with any leaves that are left, they go on the compost pile along with the spent garden plants and year-end grass clippings to make the perfect compost blend. (It’s good to cut the lawn a little short at season’s end to reduce moisture-related snow mold coming out of winter.)
I ran across one county in New York State (Westchester) that’s thought this through enough to start an initiative to get their residents to use their leaves on their property.
It’s called “Love ‘Em and Leave ‘Em.” Clever, eh? Check out the Love ‘Em and Leave ‘Em web site (www.leleny.org) that has all kinds of excellent tips and information.
George,
In another approach (with only a small layer of leaves) I mow/mulch them instead of raking. Once broken up, they don’t seem to blow to the neighbors. Any downside to this?
STW
Scott,
Mowing them in is the way to go. Mow them in often enough before you get too much of a backlog and go over them twice if the first mow doesn’t chop them into small enough bits. If you have a ridiculous amount of falling leaves, it’s possible that enough of the bits might back up enough to shade out the grass. That’s the only downside I can think of. But if you can see the grass after you’re done mowing, that’s fine.
George
George- How I wish so many more folks would use his method. Free nutrients, free exercise, fresh air…what could be better? I have been turning my leaves and can’t wait to get them on prep mode for my new for 2013 cutting garden.
Thanks fo thhe good article! ca
I’ve been using leaves to top-dress my some of my veggie garden beds over the winter and it works great to keep the beds free of weeds. Otherwise out here in “weed heaven,” aka the country, evil weeds can completely colonize a bed between the time the crops are pulled in the late summer or fall and when I plant in the spring. In the spring, I can either turn them in to the bed, or leave them on top and plant transplants right through the mulch.
I don’t have enough leaves to cover all my vegetable beds, so I may be scrounging some leaves from those people who bag that resource and put it curbside.
Margaret,
I also sometimes use all of my leaves and bring in more from the neighbors. They’re not trash to me…
George
Chris,
That’s the way I see it, too. We’re definitely in the minority, though. Almost everyone is blowing their leaves out to the curb at the moment or ignoring it altogether.
George
Great Article! I found it researching a possible blog post, as morbid as it sounds I was hoping to find statistics on how many people are injured every year because they are hiding/playing in a curbside leaf pile and a car drives through it…cars, curbside, leaf piles and accidents all in one article—you popped right up!
Seeing that you are in PA and we are in Ohio, I suspect you share our dilemma of too many leaves at once.
We run a junk removal business and we often get called for yard cleanup jobs (yes, we compost everything possible but as you noted that robs the location’s environment and burns gas in our truck). Do you have a rule of thumb for how many leaves are too many?
If using them on like mulch around plants and beds, how deep should I layer them?
Thanks. We really do waste too many of an excellent (and free) resource, in my opinion.
As for how many leaves are too many to mow in, if you can still see some grass, that’s fine. Even a light layer that just covers the grass is OK. It’s when the leaves completely cover the grass and begin to pile up that it becomes tough for mowers to adequately chop without clogging.
Bigger mowers and mulching mowers can handle a bit more leaves than small, side-discharge ones. That’s really more of the limiting factor than how many leaves the lawn can “absorb.” A good quantity test would be that if you can see grass blades sticking up in the end, you haven’t overdone it with leaves. The main down side of leaves on the lawn is that they have the potential to mat down and shut off sunlight to the grass as well as trapping moisture that can encourage diseases such as snow mold.
That’s why it’s important to mow the leaves — to reduce them to bits that fall among the blades. Go over a leafy lawn twice with your mower if you have to. Fragments between the blades will break down over winter.
As for leaves as mulch on bare ground, 3 to 4 inches is the maximum around trees and shrubs, and about 2 inches is ideal in flower beds and on top of vegetable gardens. They’ll stay in place much better if you chop them with a mower or leaf vac before applying to the beds.
I also save several bags of chopped leaves to use in spring between the tomato plants, peppers and annual flowers. Leaves add nutrients and organic matter as they break down, but they also break down significantly faster than wood or bark mulch, which means they don’t give as good of a long-term weed control.
If you find the leaves are all but gone partway through the growing season, either add more of the leaves you’ve bagged or top the leaves with a light layer of bark or wood mulch. Although it’s a little extra work, a good game plan is to top beds with chopped leaves in the fall and then top those with a light layer of bark or wood mulch in spring. It’s about as close as you’ll get to the way that nature “mulches.”
Happy leafing.
George
Thank you George for this information. Have always thought you should rake up leaves on your lawn because it will kill it but that is only if it is a load of leaves. Thanks again for the education ! Always enjoy reading your emails.
Have a great Fall !
Happy Fall George !
Just put in a lovely all-native garden this Spring and it is getting a lot of leaves from trees near it. Unfortunately most of the trees are Black Walnuts. Due to the Juglone these trees give off, shouldn’t I rake up the leaves so plants don’t die ? I know a lot of native plants don’t mind black walnuts but can’t pick and choose obviously.
Thank you and have a great end of the year.
Debbie
Debbie,
Yes, since juglone is in all parts of the black walnut tree, it’ll help to rake fallen leaves out of your flower garden. Accumulated leaves can leach juglone into the soil via rain and by breaking down in it. Leaves and nut hulls are two main ways walnuts launch this self-protection system.
The other way is when sensitive plants come into direct contact with walnut roots. There’s not much you can do about that if your garden is close enough that tree root will encroach the space. In most trees, roots spread out at least twice as far as the above leaf canopy.
Wilting is typically the first sign of juglone problems. But keep in mind that plants can wilt from the root competition of any tree. Big tree roots can mine moisture more effectively than perennial plant roots, so any wilting you see could be from soil dryness.
How to tell the difference? A good soaking will correct wilting from dryness, while wilting from a juglone problem will continue to worsen despite a watering.
Penn State Extension has a good online list of plants that are both sensitive to and resistant to black walnuts if you want to compare the list to what you planted.
http://extension.psu.edu/plants/gardening/fact-sheets/trees-shrubs/landscaping-and-gardening-around-walnuts-and-other-juglone-producing-plants