Time for a New Compost Pile

If it's spring, it must be time to start a new compost pile. Here are some of our favorite ingredients: leaves collected in the fall and chopped fine in the leaf grinder, coffee grounds from Starbucks, and something new: horse manure.

For years I've been passing a small riding stables on our usual route to the in-laws in Annapolis but it only recently occurred to me to ask the owner if I could have some of her horse manure for my compost. She was eager to oblige and now lets me fill all the buckets I can handle.


I filled four large trash cans with chopped leaves waiting for this moment. A layer of leaves starts the pile.

Then I add a bucket or two of horse manure.

Plus about 10 pounds of coffee grounds. My local Starbucks packs the grounds along with the used filters (they'll compost as well) in the foil bags that their coffee beans arrive in. It's good to have a wide variety of materials in your compost pile, including kitchen scraps, garden debris, dryer lint, pet hair, shredded cardboard. If you have time, chop things into small pieces.

Toss a shovel full of soil or last year's compost to spread some bacteria in the pile to get the process started. Water each layer so it has the consistency of a wrung-out sponge: not too wet, not too dry. The organisms in your compost pile--bacteria, fungi, protozoa, mites, sow bugs, earthworms--need moisture as well as oxygen to survive.

We are aiming for about equal proportions of "brown" or carbonaceous ingredients such as leaves or shredded newspaper and "green" or nitrogenous ingredients such as manure, grass clippings, coffee grounds. But if you have any doubts, it's better to have more "browns" than "greens" to prevent the pile from getting too wet and driving out the necessary oxygen. What you don't want is an anaerobic pile: it will smell horrible.

Temperatures in the pile can exceed 140 degrees, indicating that your bacteria are busy. After the temperature peaks and begins to subside, turn the pile to inject more oxygen. We'll probably be turning this compost into our garden beds in the fall.

For a full tutorial on composting, take a tour of my Monkeysee video.

A Little Compost with that Latte?

Did you know that Starbucks has a corporate policy of making its used coffee grounds available free as a soil amendment or composting ingredient?

For months I've been working up to introducing myself to our neighborhood Starbucks and starting regular pickups of grounds for my compost pile. A fellow gardener here in the District of Columbia is a prolific composter and coffee grounds have become one of his primary ingredients. He attached a trailer to his bicycle and pedals around town, stopping at various Starbucks stores and harvesting their used grounds.

I don't plan on using coffee grounds quite to that extent. But coffee grounds do contain a fair amount of nitrogen and therefore are considered--along with grass clippings and other kitchen scraps--a "green" material to be mixed with "browns" such as leaves and newspaper in the compost pile. Nitrogen feeds the bacteria that heat up the pile and ignite the decomposition process.

So this week I finally introduced myself to the local Starbucks. The manager on duty looked surprised when I told her what I wanted. She'd never heard of the Starbucks coffee grounds policy, and apparently no one had ever asked for the used grounds at that particular store before. Nevertheless, she took my contact information and promised to have a bag of grounds ready for me to pick up later in the week.

Imagine my chagrin when I entered the store at the appointed hour and found a different manager on duty. No grounds had been saved for me. I was very disappointed. But then this particular manager--Vanessa is her name--explained that she had seen my note and knew all about composting with coffee grounds. She had moved from a Starbucks location in California where they are quite used to giving away their used grounds to gardeners. "We even have tags that we put on the bags explaining how to compost with the coffee grounds," she explained.

Even though the grounds had not been saved for me as promised, Vanessa would not let me walk away empty-handed. "We have some bags of expired beans," she said cheerily. "Would you like me to grind them up for you?"

You bet I would. So I waited while Vanessa ran 15 pounds of coffee beans through the grinder and bagged them for me. Here you see them waiting to be mixed into the compost pile I started last fall.

Coffee grounds are slightly acidic but entirely organic matter, making them a suitable soil amendment all on their own. Once the micro-organisms start feeding on them, the nitrogen contained in the grounds is slowly released to feed your garden plants. Coffee grounds also contain potassium, calcium and magnesium. Both Starbucks and Sunset magazine have run tests on coffee grounds to identify specific nutrients.

Unless it's decaf, I don't drink coffee anymore. But I can easily see these free coffee grounds becoming addictive. Thanks, Vanessa. And thanks, Starbucks, for thinking of us composters.

My New Forked Spade

How do you like my new spade?

I got tired of my wooden-handled model breaking in winter, usually around the compost heap or digging up carrots or wherever the earth was a little bit frozen. So I ordered this one from Lee Valley Tools. It's stainless steel with a plastic cover and grip, guaranteed never to fail. It set me back a bit, but I figure it's worth investing a little extra in a tool that will probably last a lifetime. Along with my stirrup hoe, I use the forked spade around our kitchen garden more than any other tool.

I thought I'd baptise the new spade in our compost heap. It was frozen almost solid on top and around the sides, but the stainless spade made quick work of turning the pile into a neighboring bin. Not much decomposition going on this time of year with temperatures steadily below freezing. But you'd be surprised at the number of earthworms still active at the bottom of the pile. I'll bet they don't like me turning their home upside-down in the middle of winter, but I'm sure they'll find a warm spot to hang out.

While I was at it, I tossed a year's worth of shredded personal documents into the bottom of the pile. It's nice to know that our bank statements will soon be feeding the tomato plants.

Can Compost Save Planet Earth?

That's the question I posed in my Powerpoint presentation yesterday at the Historical Society of Washington. And about 60 determined souls braved arctic temperatures and bitter winds to show up at 10 am to hear it.

During two years as president of D.C. Urban Gardeners, I never ceased to be amazed at the number inquiries about composting. And not just from gardeners. No, there are many renters and apartment dwellers out there who want to do something good for the planet by recycling their kitchen scraps. They want to know how to compost.

Yet even here in the nation's capitol we are woefully behind in responding to this pent-up urge to compost. Unlike jurisdictions such as San Francisco, which has implemented curbside recycling of food waste and dirty paper for composting, there is virtually no public composting program or infrastructure in the District of Columbia.

In fact, crews have been busy all over town lately sucking up leaves into big trucks and hauling them off presumably to a landfill. In the past, some of those leaves have been composted on a trial basis and made available at a municipal transfer station that could take you half a day and a satellite imaging system to find.

So people want to know not just the basics of composting--what kind of bin to use, how to avoid nasty smells and rats--but where they can take their food scraps to be composted, or, if they are composting with worms, where they can take the finished castings. (Okay, how about spreading them around in the nearest curbside planting?)

In other words, people need help, and the city is not offering any.

The District is in a hard place--we are a small city/state crowded on all sides by Virginia and Maryland with not a lot of big open lots for composting. But my reading is that so many people are ready to start composting, something will have to give soon.

Note: There are many composting resources linked from this blog, starting with a series of videos detailing how to compost. For a whole list of other places where you can learn more about composting, composting with worms and composting bins, scroll down to the lower right.

The Gift of Eggs

And I don't mean figuratively, but quite literally: Someone has been leaving eggs on our doorstep.

The first carton appeared a couple of weeks ago and we chalked it up to one of those curious things that sometimes happen in the big city. But then we found a second carton of eggs (pictured here) sitting on the steps just inside our front gate.

We suspected that our mysterious egg gifter might be our farmer friend Mike Klein. We've been pestering Mike about getting a delivery of some of his farm-fresh eggs. Maybe we'd be seeing an invoice soon?

But when I e-mailed Mike, he insisted it wasn't him. "I'm not that generous," he said.

Then last night we found not one but two quart-size cartons of soy-based yogurt--one stacked on top of the other--sitting on the same concrete step where we'd found the last batch of eggs. What the...?

My wife suggested I check the "sell by" dates on the yogurt and the eggs. Perhaps these weren't so much gifts as just cast-offs someone was trying to dispose of with us. Sure enough, the "use by date" on the eggs had expired. I did not check the yogurt: that went directly into the trash.

Then our thoughts turned to the woman we met on the sidewalk one day who recognized me as "that guy who composts." I was thrilled to be recognized. Then the woman revealed that for her this was no brush with fame. She asked if we would accept her banana peels for the compost pile (I guess she eats a lot of bananas.)

Since that time, we occasionally find a plastic grocery bag on our stoop containing banana peels. Could she have graduated to leaving eggs and yogurt? Who buys so many eggs and so much yogurt that they need to dispose of whole cartons?

So far we have kept the eggs over the objections of our daughter, who fears they might be poisoned (such is the world we live in, I guess). If you are the giver of these items and you are reading this, you should know how much we appreciate the thought behind your donations. But you should also know that we do not compost eggs or yogurt. The eggs we plan to hard-boil. If I had a pig, I would feed the yogurt to it. But in the absence of a pig, the yogurt unfortunately is headed for the landfill.

Otherwise, the mystery continues....

Compost Ready?

Even experienced composters sometimes get it wrong--knowing when your compost is ready to use.

Thankfully, Chris Elliott is here to show us how to test for perfect compost doneness.

140 Degrees

This is a mark of achievement for a home composter, what is called "hot" compost. There really was steam rising from the pile this morning, and if you peel back the top layer, a blast of heat hits you in the face.

At this temperature, the pile should decompose fairly quickly. Mostly it is grass clippings recently collected from the lawn and an equal measure of shredded leaves saved from last fall. Thus, equal parts "green" and "brown." The heat comes from all those thermophilic bacteria in the pile, chomping away on the organic matter and multiplying like mad. They will continue to generate heat like this for a few days as long as there is an abundance of nitrogen (the "green") in the pile. Then activity will slow down and it will soon be time to turn the pile to stoke it with more oxygen.

Of course you don't have to compost this way. Things will break down if you just throw them in a heap and leave them alone. But that takes months longer and I like to know that I will have plenty of compost to work into my vegetable beds later in the season, when it comes time to planting our fall crops.

Ain't nature grand?

Trash Can Composting

Here's our friend Matt shredding grass and leaves in a trash can to make compost. For you suburbanites out there this may be totally unnecessary: You have a big back yard in which to construct your composting system.

But for us city folk, ingenious steps must be devised to compost in small spaces, especially to keep our kitchen scraps away from the local rats.

Garbage cans are a bit smaller than what the composting experts describe as the minimum size for an "optimum" compost pile. That would be three feet wide, three feet deep and three feet tall. But in fact compost will happen anywhere, even in a crack in the sidewalk. You can bag leaves in the fall and come back in a couple of years and even those bagged leaves will be turning into compost, the ideal amendment for our organic vegetable beds.

When a neighborhood learning center near my home--the Emergence Community Arts Collective--asked me to teach a course in composting that would result in actual compost, I proposed the trash can method. Teachers at one of the local schools employ several trash cans to turn their garden debris into compost. There's plenty written about it on the internet.

I had the arts collective procure a metal trash can (tougher for the rats to get into--I hear they are often available on Craig's List). I came by and drilled a series of drainage holes in the bottom, then more holes around the sides of the can for aeration. After watching my Power Point presentation on the hows and whys of composting, a small group of eager composters went to work in the yard, filling bags with last year's leaves and pulling as much green grass as we could find.

A good compost requires a proper balance of "green" materials, such as grass clippings, and "brown" materials, such as fallen leaves. They aren't always available exactly when you want them. Sometimes it pays to store leaves over the winter for a time when enough grass clippings become available to create the right mix. But if you poke around the neighborhood, you often will find old leaves waiting to be collected in an alley or blown into a pile against a fence. Kitchen scraps and coffee grounds from the local barista also make for good compost. Composting is a good way to recycle your newspaper or shredded personal documents as well.

The students were amazed to see how the bags of leaves they collected reduced to very little when we shredded them with our electric weed whacker in the trash can. We used the line trimmer just like a hand-held blender, plunging it into the leaves and moving it this way and that. We collected more leaves. And more leaves. And more leaves. And since we didn't have a mower, we collected the grass by hand and shredded that as well.

When it was all done, our trash can was a little more than half full, about equal parts chopped leaves and grass for a quick-acting compost. One of the students had brought some shredded paper, another had a bag of kitchen scraps. We mixed that in as well, then added a couple of large pitchers of water until our mix was just damp, about the wetness of a wrung-out sponge.

"By tomorrow, this compost will be hot," I assured the class. I knew that bacteria quickly would begin to feast on the nitrogen in the grass clippings, multiplying like crazy and raising the temperature of the heap. My students looked dubious. But this morning I visited the site. The ambient temperature is 40 degrees--just eight degrees above freezing--but inside the trash can, things are already toasty.

Swarming With Earthworms

Today was the first time I'd turned my compost pile since sometime back in 2007. I just assumed there had not been much activity in there, what with the winter freezes and all.

But apparently my earthworms couldn't wait to get started. With the first shovelful I uncovered a swarming mess of them, hard at work turning all that garden debris and grass clippings and chopped leaves into something I can dress my vegetable beds with.

Turning the pile injects oxygen, which stokes the bacteria in there to get them working faster. Also, you don't want your compost pile to turn anaerobic, which invites a whole other breed of micro-organisms that will make the pile smell like garbage.

My pile is standard size: about three feet in each direction. It takes me about 45 minutes to move the whole thing into an adjoining bin, where it can finish the decomposition process. Not in time for my spring plantings, but I'm guessing this will be fine fodder for the tomato plants.

Turning compost is a contemplative act. Ronald Reagan retreated to California to chop wood. George Bush likes to clear brush on his Texas ranch. Me, I just put on my windbreaker and work up a little sweat turning my compost. For any of you organic food lovers, this is where it starts: making dead stuff into life-giving soil

At times like these, when it's just me, the earthworms and the occasional fire truck screaming past our urban plot, I try to think pleasant thoughts. Sometimes I am bothered by a rumination on the whole sorry story of human venality and destructiveness. I keep shoveling. Composting brings me a little closer to planet earth. It's one thing I know I can do and not go wrong.

Winter Compost?

As promised, I spent some time chopping an entire case of celery I found on the sidewalk recently and turned it into my compost pile. In fact, this seemed like a good time to turn the whole pile, shoveling it from one bin into a neighboring bin, tossing in the celery as I went along.


Composting is a slow, meditative act and good for the soul. It is perhaps the closest thing I have to a religion. It affirms my faith in the natural process when otherwise there is so little to celebrate about man's role in the order of things. Humans are a destructive force on the planet. Composting is a daily act of creation.


The compost pile I started last month was running hot (more than 110 degrees) for a couple of weeks, then it went cold. That means the bacteria that heat the pile have less to feed on, or they need more oxygen. Turning the pile supplies oxygen. Celery gives them more to feed on. Ideally, I would toss is a bag of grass clippings to speed things along. Unfortunately, my lawn mower is broken.


Composting in winter is a struggle. Life slows in the cold. Some micro-organisms survive at temperatures near freezing. But the process mostly grinds to a crawl. If it gets cold enough, the pile will actually freeze. Last year I broke the handle on my forked spade trying to bury kitchen scraps in the compost pile. (They just don't make spades like they used to.)


In that case, the kitchen scraps will stay well preserved until the sun climbs back in the sky and things warm up again. I'm guessing I will have some excellent compost to spread on the garden beds when it comes time to plant seeds in the spring.

The Beginning of Food

Neighbors might have thought it strange, a man wheeling bags of leaves and grass clippings up the sidewalk. But in my travels yesterday, I noticed a landscaping crew cleaning the area around a huge apartment complex down the street.

There were at least six workers busy mowing grass and blowing leaves and the sight of it I stopped me in my tracks: compost.

I suppose the workers thought I was crazy, pointing, waving my arms, jabbering away in fractured Spanish--indicating however I could that I wanted their big bags of lawn refuse. They looked at me like I was daft, then looked at each other as if to say, What is this guy talking about? But we soon had an arrangement: they would continue bagging the grass and leaves while I ran up the street and fetched my hand truck.

In fact, the captain of the crew spoke enough English that we could compare notes on composting. He agreed that I had a good mix of materials and that by next year (or maybe the year after, he seemed to think) I'd have some great soil amendment. "All organic," he said, nodding.

The trees here still haven't shed all their leaves and we have great colors despite months of drought. Normally I would be driving around the neighborhood in the coming weeks, snatching the leaves people gather and bag from their lawns and place at the curb for pickup by city crews. Brown leaves, a great supply of carbon for the compost pile, are difficult to come by in the spring and summer if you haven't saved a stash. The grass clippings, or green material, contain the nitrogen that stokes the composting process.

All of this may seem off the topic of food. Yet it is essential to the food we eat. Trees draw nutrients from the ground, which find their way into the leaves, which then fall back to the earth. Nitrogen is essential food for vegetable plants. Compost feeds the soil with organic matter, supporting an entire ecosystem of small creatures who transport nutrients to my carrots and beets and lettuces and tomatoes and make the soil a living, hospitable environment for things to grow. In the end, those very same nutrients find their way into our bellies as well.

I made several trips back and forth with my bags of loot. The landscaping crew, once they understood what I was doing, pitched in to help. Normally they use a big vacuum to blow the leaves into the back of their truck. But this time they gathered the leaves and stuffed them into more bags so I could wheel them home.

Every bit of compost I make myself means compost I don't have to buy, compost that doesn't have to be trucked into the city from somewhere else. It also means leaves and grass clippings that don't have to be trucked out of the city in the back of a landscaper's truck and dumped who-knows-where. We love the idea of nature recycling itself right here in the neighborhood and feeding us in the process.

Slow Cook on Video: Composting

I know this is the moment you've all been waiting for: The Slow Cook on film.

Earlier this year I agreed to shoot a series of short takes on the steps involved in composting here in my garden in the District of Columbia. They've been edited and made available free on-line by Kowlera Media as something called "Monkey See." It's like a video version of "About.com," covering every imaginable topic, only with moving graphics.

My part of the process was to write out a script and have everything ready to film when a young man from Kowlera Media showed up with his camera and remote microphone. We then filmed 15 clips: setting up a compost pile, what kinds of material to use, how composting works, how to use it in your garden, composters for urban settings and more.

This is the first time I've seen it since we did the filming--or should I say video-ing. It's pretty neat, and you can watch it all here.