Everything You Know About Composting is Wrong by Mike McGrath (Transcript)

Mike McGrath at TEDxPhoenixville

Full text of You Bet Your Garden host Mike McGrath on Everything You Know About Composting is Wrong at TEDxPhoenixville conference.

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Was it Chekhov [Anton Chekhov] who said that if you bring a leaf blower on stage in the first act you have to use it by the third act?

The timing for this event is so appropriate. We’re here in the fall, and I’m going to talk to you about composting.

A lot of people schedule composting talks in the spring. A lot of people start composting in the spring. They buy a compost bin, and along with the bin comes detailed instructions which are about the size of a index card, and it says on one side: “Things you can include: grass clippings, leaves, kitchen waste, old newspapers, your junk mail.”

On the other side, it’s things you should not include: “Dog and cat feces, old car batteries, people who need to go for a ride behind the Philadelphia Airport and get to know the fishes in the marshes better. Don’t compose them.”

And so well meaning people will get a compose bin in the spring, and will fill it with their kitchen garbage. It says, it’s right there, on front of the card. You can compost your kitchen garbage. So they fill the composter with kitchen garbage, and they’re very happy with themselves. Al Gore is somewhere giving them gold stars.

And they’re waiting, and they’re waiting, and at the end of the season they take the composter off, and they have a big pile of kitchen garbage. It has not improved in quality, in any way, over the summer, and that’s the big lie of composting. People come to composting to get karma points. They want to stop throwing away their kitchen garbage, and you can stop throwing away your kitchen garbage.

But composting is an imitation of nature and nature does not make big piles of trash, and garbage out in the woods, and neither should you. So this is the perfect time of year to start composting.

Thanks to our trees. If anything will save us, it’s trees. Trees are the original solar panels. Every year, every season, the roots of trees reach down deeper into the ground than they went the year before, pulling up nutrients, pulling up trace minerals, which the roots couldn’t reach the year before. They send them up to the canopy, where the leaves that contain these nutrients are super charged by photosynthesis.

Doubling and tripling the nutritional content, and then, because nature realizes that we’re a little slow, at the end of the summer, drops the leaves down at our feet. “Hello, look at me, here I am. I am nutrient-dense.”

So, what does the average American man do? He blows all this nutrient dense material onto his neighbor’s driveway.

The neighbor comes out, and he blows the leaves back onto the other neighbor’s driveway.

Now this is not meaningless, this is not wasted time. Here we have two American men who are being occupied, who otherwise might get into real serious mischief.

But eventually, even an America man is going to realize, “Harry and I have been blowing these leaves around for three months and they’re still on the ground.”

So that’s when the American man digs out the rake and then he goes to the hardware store, or Home Depot, and buys SPBs, Stupid People Bags, which are brown paper bags, that tell your neighbors, “I’m too dumb to save my leaves. I’m paying extra to throw them out.”

So that’s the first lesson today. SPBs are like unattended pens, they’re yours. If there’s no one around to protect the pen, it belongs to you.

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Same thing for leaves put out at the curbside. This is everything you’re going to need for your garden. I guarantee, you will never get to the end of a gardening season, and go: “Boy, I wish I had fewer leaves, or had made less compost.”

So don’t be afraid to rustle up SPBs.

But, as the leaves come down, these tools can become valuable. Because if these American men would look in their garage, or their basement, there’s probably a box with a conversion kit, and I think it’s called “The Conversion kit” because when you read this part, you finally get religion.

But you can replace the blower with a vacuum, and now the most aptly named power tool in the history of America no longer blows. You can use it to suck up your leaves. Virtually every electric leaf blower comes with one of these. There’s guys who have leaf blowers who are 15 years old, these are in mint condition, down in the basement.

And a collection bag. You hang it from your shoulder, and the first thing you will notice as you use this to rustle up your leaves, is there’s no bending. Bending is for chumps. If you are doing hard work while gardening, you’re not paying attention.

So you stand up, you suck up your leaves. Inside every one of these machines, and the nice thing is these things should become even better over the years, you may be able to see it. There’s a metal impeller in here, a metal wheel. So as you suck up the leaves, they get shredded, and dropped into the collection bag.

Take the leaves out of the collection bag. You can use those to mulch your garden beds right away, preventing any weeds that would form over the winter, and in the spring.

But what you should do with your first run of leaves, is make a big pile, and yes, the big question is always: “Do I have to shred my leaves?”

And the answer is: “Yes.” Whole leaves have a tendency to matt down into a darn good imitation of a tarp. What people don’t realize about trees, trees are not benign, trees are solar collectors, trees give us everything we need to have a fabulous garden the following year.

But trees are bullies. Trees do not want any competition. When they drop their leaves, yes they’re preparing themselves for winter, they’re sealing off the parts of themselves that would be damaged by cold, but they’re also smothering all the little children on the forest floor. They are making sure that they’re kings of the block. You have to be a good plant to be able to survive leaf fall.

Now over time, in the woods, with wind, and deer, and winter those leaves get shredded. But when they’re first put down, they are competition smotherers. So we’d want to avoid doing the same thing, so the only thing we have to do with our leaves is shred them.

And if all you do is shred up your leaves, put them in a contained bin, it can be as simple as a big wire enclosure, it can be a fancy, dancy composter you buy, it can be tumbler, it can be your old tomato cages. I’ve worked out a sequence, whereby this time of year — first of all, the stink bugs have been violating my tomatoes for the past two weeks, so I’m sick of looking at that carnage in my garden, and it’s also time to be done with tomatoes.

So you take your old tomato cages, get rid of the tomato plants. You can leave them in place, put in something else, just start filling them with shredded leaves. At the end of the fall, make sure you’ve shredded up enough leaves to fill up everything like this, because again, you’ll never get to the spring wishing you had done less.

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Now it may seem like a scam, in the beginning, because the leaves will shrink down in size. By the time we get to Christmas, your leaf piles will probably be half their size. By the time we get to spring, they’ll be half again smaller, but you still won’t see any compost. All you will see is unshredded leaves, and you’ll think I’m a fraud.

Well, yes I am, but not about this specifically.

The dirty little secret of composting is it’s always done on the bottom. Why? Because that’s the least convenient place for us.

So just lift off these tomato cages, or just take a rake, or a broom, if you have a big open pile, and very gingerly, remove all the leaves that still look like leaves. Down at the bottom, if it’s been a freezing cold winter, if you’ve done nothing to move this process along, you’ll have a beautiful pile of rich, black compost.

Every agricultural study ever done says that two inches of yard waste compost made with this incredible, nutrient-dense energy, harnessed by trees through their leaves, is all any plant needs to be fed, and protected from disease for an entire season. Two inches of compost, that will take care of an American lawn. That will take care of your vegetable garden. That will take care of your flower garden. I would say you could brew it, and make tea out of it, and you can, but I wouldn’t drink it. I would use the tea to feed my plants. It is everything your yard and garden needs.

Now, in the spring you’ll still have uncomposted leaves. What are you going to do with those? Well, one of the inconveniences of the fall leaf drop is right after the leaves come down for us to harvest, it gets cold. As many of us know all too well, cold slows down biological processes. So you get your least composting action over the winter.

If trees were more considerate, they would drop their leaves in the spring. But they don’t.

But when spring arrives, you take those uncomposted leaves, mix them together into a big pile, they will compost down very quickly, thanks to the warm weather.

Now, what do you add to your leaves to move things along? I had an epiphany once in Holland. I was over there for an agricultural convention, and Holland will make you realize that Americans know nothing. Because every schoolchild in Holland speaks 16 languages, fluently, and we can barely speak English. No, that’s true.

I got on a tour boat in Holland, and the girl who was doing the tours would speak to everyone in their own language. There was a Japanese couple, she said she could do Japanese, French, German, no problem. People in front of us were Brits, and they said English.

And then my friend, and I got on the boat, and we said: “English” too. And she goes: “Oh, I’m sorry, aren’t you American?”

And I go: “Yeah, what’s the difference?”, and without missing a beat she goes: “I’ll talk faster, and slur my words.”

So I’m at this big banquet, as we’re getting ready to close down, and I have a Dutch high school girl, who speaks 18 languages, and a French guy over here, and we’re trying to converse about composting. She turns to me and goes: “He wants to know, why you don’t like your leaves.”

And I go: “I love my leaves. What is he talking about?”

And she goes: “He said you mix garbage in with them.”

It turns out that the entire French bedding plant industry, their entire system of horticulture, is based on what they call “leaf mold” alone. They collect and shred every leaf they can find, just let it sit out, don’t add anything to it, and that’s what they use to produce their bedding plants, in the spring.

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So if you’re confused about what to add to your shredded fall leaves, don’t add anything. If leaves alone did not compost, the Earth would be covered 500 feet deep in unshredded leaves. “Everything rots”, as those of us of an advancing age know all too well. They will rot. Shredding them is the only unnatural thing you have to do, to move the process along.

Don’t add your kitchen garbage. I realize that is an unpopular statement, but your kitchen garbage is cold, meaning it has no nitrogen. The real dirty little secret of compost is if you mix up kitchen waste and fall leaves, it’s only the fall leaves that become the finished compost. The right kind of kitchen waste can move the process along. Small amounts of the wrong kind of kitchen waste won’t hurt anything, but it is only the leaves that become the compost, which is why you must save, and shred as many as possible.

There is one exception, one thing in your kitchen, that is, like myself, full of nitrogen, that is really hot, that will move the composting process along. It’s also rich in calcium, phosphorus, and potassium, and that’s coffee grounds. Spent coffee grounds add moisture to the pile. They add nitrogen to the pile. Were you to take the standard Lehigh bin — developed by J. I. Rodale at the Lehigh University, in 1942 — which is a 4-foot cube; 4-foot by 4-foot by 4-foot, filled out with leaves, mix in 5 to 10 pounds of spent coffee grounds. Believe me, coffee shops are desperate for you to come in and ask for their coffee grounds. Mix it all well.

Whoever told you to layer your compost pile failed physics. Because you don’t get a reaction by isolating ingredients, you get a reaction by mixing them. Mix up those leaves, and those coffee grounds, you can warm your hands over that pile for the next week. It will cook. It will reduce in size immediately. You may get finished compost, before the weather gets bad.

Kitchen scraps, get a worm bin. I am late to the worlds of red worms, and I am ashamed. I have a worm condo. I have a rising tower of worms now. I just asked Gardens Alive to send me four more levels. I’m building the Society Hill towers of worm towers, and all of our cold kitchen waste is going in there, where worms can turn it into the only material that might even be better than compost, nutrient-rich worm castings.

A researcher once said: “Something magical happens inside the gut of a worm. Because the material they put out their back end is more nutrient-dense than the material they took in their front end.”

But, whatever you do, whatever you take away from this, find a way to shred your leaves. Save them in plastic bags. Just mulch your garden beds with shredded leaves next spring. Earthworms will colonize that leaf litter, and feed your plans for free. Make compost from it, do both things from it. But don’t let it go to waste. We love plants all year round, the leaves only come down once a year. This is your opportunity, make the most out of it.

Thank you.


Resources for Further Reading:

The Bacterial Solution to Plastic Pollution: Morgan Vague (Transcript)

Dr. Demetra Kandalepas: Fungi Matter at TEDxLSU (Transcript)

Scott Fulbright: Is Algae the Ink of the Future? at TEDxMileHigh (Full Transcript)

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