How to build a compost pile

Pinterest

A compost pile is easy to make and doesn’t require much space. In order to reach optimal temperatures, the pile should be at least 3 feet wide, 3 feet across, and 3 feet tall (one cubic yard). That is the minimum size to generate temperatures that can kill weeds and pathogens, but smaller compost piles will also work with reduced efficiency. Larger piles work even better because their size will increase the temperature in the pile, but anything taller than 8 feet is overkill. Extremely large piles of compost are at risk for spontaneous combustion, and they are also extremely difficult to aerate properly.

To build a compost pile, start by clearing off a patch of ground. Choose a spot that’s away from trees or fast growing vines – the roots from these plants can infiltrate the compost pile and suck away nutrients. It’s also important to remove any weeds or seeds from the area – if your compost pile fails to get hot enough, these seeds will get mixed into the finished product and may germinate when you use the compost as potting soil or fertilizer. The best ground for a compost pile will be slightly elevated and have excellent drainage. It is also a good idea to locate compost piles away from inhabited buildings, gardens, or silos because they can attract insects.

If you plan to build a very large pile, be sure to put footpaths every 8 feet or so that are wide enough for a wheel barrel. Then, line the ground with groundcloth or plastic liner to protect against root intrusion. If there are moles, groundhogs, or other burrowing animals in your area, you may want to put a layer of chicken coop wire or hardware cloth too. Avoid putting the compost pile against a wooden fence or deck – the compost can stain wood and may encourage rotting.

After you pick out the perfect spot, it’s a good idea to gather separate piles of ‘green’ and ‘brown’ organic matter. Green waste is high in nitrogen – it includes things such as vegetable scraps, fresh grass clippings, and manure from herbivores. Brown waste has a high concentration of carbon – it includes things such as leaves, dried grass, and twigs. There are certain things that you should NOT put in your compost pile. Before you start construction, please review our section on ingredients that don’t belong in a compost pile.

Break these components into very small pieces, but save a few sticks for building support structures. The more surface area your ingredients have, the faster they will decompose. Start with a layer of brown waste and leave plenty of airspace at the bottom of your compost pile – this will help with drainage and also create a chimney effect of airflow.

Use your piles of organic material to create alternating layers of brown and green waste. Sticks and split logs are important for building the pile because they will provide support and hold everything together. Use twigs in the compost pile the same way that you would use them to build a campfire – with alternating rows and columns that allow air to flow through easily. The center of the pile will have to support the most weight, so you may want to use the thickest sticks in that area. If you plan on turning your compost pile regularly, don’t worry so much about structure. Instead, you may want to feed your sticks through a wood chipper to get the most surface area and the fastest decomposition.

Animals and pests are often attracted to the smell of rotting garbage. If you put a lot of green waste into your compost pile, it can be a very good idea to put fresh waste near the bottom and under sticks or thorns. Such a barrier will do a good job keeping raccoons and skunks away, but insects and rodents will often be able to sneak through very small openings, and snakes may also move into the pile to feed on them. Because of this, it’s a very good idea to wear protective clothing and make plenty of noise to scare animals away when turning a compost pile.

Keep building your compost pile until you run out of materials. Each layer can be as thick or as thin as you’d like to make it. The best way is to use thin layers of green material (2-4 inches) and thicker layers of brown materials (5-7 inches). If you don’t have any green waste available when building your pile, it may be a good idea to add one of the following as a compost activator: manure from a grass eater (ie; cow, sheep, goat, llama, hamster, gerbil, rabbit, chicken), alfalfa meal, bloodmeal, bonemeal, coffee grounds, or even just soil from another part of your yard. Cat and dog droppings are not recommended because they may carry disease. Horse manure is not recommended because it has a high number of weed seeds.

Depending on your climate, it may be a good idea to cover your compost pile with a tarp. This is necessary if rainfall or snow is heavy in your area, because excess moisture can slow down the composting process. Moisture should be in the same range as a wrung out sponge – if you can extract water by pressing or squeezing the compost in your hand, then there’s too much moisture. There are other ways to protect your compost pile from the weather, such as placing it under a tree or under a roof overhang, but they have drawbacks (trees rob the compost pile of nutrients and building a compost pile against a building can attract pests inside). To get around this, you may want to take advantage of dead trees or unoccupied buildings, such as a garden shed, patio, or arbor.

The final step is waiting. Let nature take its course, and before you know it, you’ll have a pile of rich, black gold (no, not the kind that you can put in your gas tank, but the kind of natural fertilizer that plants thrive on). Finished compost has a carbon to nitrogen ratio of about 15:1. The resulting material is coarse, crumbly, and spongy – a perfect mulch for absorbing water and gradually releasing nutrients into the soil.

{ 27 comments… read them below or add one }

John June 12, 2009 at 4:58 am

Can vegetable oil used for frying be added to compost?
Thank you for a most helpful web page!

————-

Although it’s technically “vegetable,” I wouldn’t add vegetable oil. Any kind of oil or grease or fat tends to gum things up, and can also attract pests and rodents. So no, don’t add new or used vegetable oil to the compost pile.

Reply

Robert DeMoura June 23, 2009 at 9:36 am

I have my compost near my porch and it smells is there anything I can do about the smell………

—————-

If compost stinks, then there is typically something wrong.

1. If it is too wet, it sometimes stinks. So let it dry out, if so. Should be the dampness of a wrung out sponge.

2. If you have too many nitrogen rich materials and not enough carbon, it can stink. So add a lot more dried leaves. Or shredded newspaper if you don’t have any leaves.

Reply

Joe June 27, 2009 at 1:16 pm

I have a compost turner, and would like to know the optimal temperature to turn the compost.

———–

I’m not sure if I understand the question. In general, I guess I would say that if you are measuring the temperature and you’re getting good and hot readings, then I would probably leave it alone for a few days until the temperature starts to get lower, and then mix it up again.

I don’t think you can really say that there’s an exact temperature that you should shoot for, or you should turn the compost at.

It’s a little bit more art than science, in my opinion. So I’d just keep testing what’s working best for your particular pile or bin.

Reply

JOHN CRAWFORD September 19, 2009 at 3:02 am

Hi
I have a large lawn and I store all my grass clippings in a pile and have begun a composting area by stacking up hay bales and filling the area with the clippings. I added a compost accelerator and it appears to be working well and generating plenty of heat. My questions are;
1. 95% 0f the material will be grass clippings, is that OK?
2. how do I know when the process is complete? I intend to use the compost mainly as a additive to my vegetable garden.

——————–

In general, a variety of materials will often compost better than a single material. However, if you are generating heat, then you’re doing it right! So keep doing what you’re doing.

When the compost starts to finish, it will cool off and will no longer generate the kind of heat that it does when it is actively breaking down. So that will be one sign.

But you can also recognize finished compost by how it looks. It looks like rich, fertile soil. And you shouldn’t be able to recognize any individual parts of the compost anymore, other than a few chunks of sticks or something like that. Once it looks like that, then you’re done.

Reply

Lucy September 26, 2009 at 7:39 pm

Is it ok to use shredded papers in our compost pile? I just started today on our compost pile but what I have the most is greens and not much of brown, dry items to add to our compost pile.
But I have a whole bunch of shreded papers as in old black and white reciepts. Would that be ok?
Thank you for any help.

———-

Yes, shredded paper works fine as a carbon source for your compost pile. You just want to avoid slick, colored papers. White paper is fine, and newsprint is fine.

Reply

April Emigh August 1, 2010 at 9:19 am

Is it possible to compost in garbage bags?

Reply

Betty Hastie May 21, 2011 at 3:15 pm

I have just done away with my compost pile. As I dug up the soil, there were white clumps that are spongy. I also had morning glory roots that keep popping up. Can you tell what the spongy substance is?

Reply

Steve May 24, 2011 at 8:24 am

@Betty Hastie, It may be a fungus but to be sure take the substance to your local county extension office and they may be able to test it.

Reply

elisha coyle August 9, 2011 at 10:53 pm

i have been “composting” for 13 years, or what i thought of as composting. throwing out vegetable & fruit scraps, tea bags, coffee grounds, egg shells, dead flowers etc… but only recently have i begun to take this more seriously and started researching what composting really involves. i didn’t know i was suppose to be putting things like leaves, ashes, sawdust, paper clippings, that sort of thing too. also i didn’t realize i was suppose to be turning it. should i start completely over? or just start doing it the correct way now? my soil isn’t black and loamy, it just looks like dirt, and it isn’t warm or hot.

Reply

Steve August 12, 2011 at 8:57 am

@elisha coyle, No, don’t start over, just mix in the items you mentioned and keep it moist. Make sure you turn your compost pile at least once a week. You will likely find your compost breaking down much quicker when a greater range of brown and greens are being used.

Reply

Maria August 20, 2011 at 1:13 pm

Just want to say thank you – your website and the questions asked and answered are a rich source of information!

Reply

Monica November 9, 2011 at 7:55 pm

I live in Phoenix and want to start a compost pile. I thought to build the containment area with cinder blocks and then add my yard and kitchen waste as I have it. Is that an ok process, to continually add? I also thought I would need to cover it with a black plastic tarp as it is now fall for us which isn’t necessarily . cold but much cooler. Should I put chicken wire down first? The area I wanted to build it on is dirt/pavement but there is occassiobally some crab grass that has grown there in the past. Thanks for your help!

Reply

Steve November 18, 2011 at 8:47 am

@Monica, Yes, cinder block will work well. You may want to drive some stakes into the holes of the block to keep them from shifting on you over time. Also, you may want to turn a few of them on their sides to create some air flow, maybe wrap those in chicken wire to prevent the material from going through. I would not put chicken wire down first. The wire will get in your way when you use a pitch fork or rake to mix it. Once it starts cooling down, covering it with plastic will help

Reply

Marci November 15, 2011 at 8:49 pm

My husband is building a 3 bin compost for me and I am wondering if I can stain it so it will last longer. I have read that milk paint is the most eco-friendly that will not leech toxins. Any other thoughts?

Reply

Steve November 18, 2011 at 8:24 am

@Marci, Yes, that is a good idea, I have also heard of olive oil being used to stain wood.

Reply

Jon H March 1, 2012 at 10:07 am

If you want to jump start a compost pile , mix in a couple of buckets of chicken manure… that stuff is like rocket fuel, so a little dab will do ya!

Reply

Shauna Del April 1, 2012 at 7:48 pm

Hi Steve,

I have an outdoor, open space compost pile which, I must admit, I have not turned for about 2 years. Do I need to be concerned about H2S when I do turn it this year? It is about 5′ x 5′ and 3′ tall.

Thanks!

Reply

Steve April 5, 2012 at 8:52 am

@Shauna Del, While H2S is toxic at high concentrations I imagine you are fine. Just don’t light any matches. You may even want to open up the center of the pile and let it breath to be on the safe side. Turn it a few times, and check if it’s finished, if so, add the finished compost to your lawn, garden or shrubs.

Reply

shaa April 21, 2012 at 10:46 am

1. Why do LAYERS OF A COMPOST PILE?
2. If manure can give Nitrogen (N), How to do P composed and K composed?

Reply

Steve April 26, 2012 at 11:30 am

@shaa, You layer in composting in order to get a good mix of browns and greens which allows the microorganisms the best environment to break down the material. As for your second question I am not sure what you mean.

Reply

cheryl April 29, 2012 at 9:10 am

I am composting in a plastic bin, bottom open. I dont turn it as the opening is not large enough on top. Its full of red worms, munching away. I suppose this is good? But what do i do now, continue adding kitchen greens to keep them happy, and when i want to use the compost, what about the worms?

Reply

Steve May 1, 2012 at 9:23 am

@cheryl, You have a few option to separate the worms from the soil. You can dump the bin on a tarp, in the shade, and separate them by hand. Or you can stop feeding them for a few weeks, allowing them to eat the remaining food in the bin, then add food to the far corner of the bin causing the worms to migrate to the food. Then you will need to harvest the soil while the worms are attracted to the food in the corner.

Reply

rockie May 31, 2012 at 8:53 pm

Im doing a compost pile for the first time. Here is how I am doing it so far.
I started with chicken wire about a 3 by 5 area. I started with browns on the bottom about 4 inches thick, followed by fresh grass clippings, a layer of straw and then apply a bag of manure. My browns are mostly leaves im raking out of the woods with some shredded paper and twigs.
Is using a layer of straw throughout too much? I’m going to work it up until it gets to be about 4 ft tall then let it bake. I plan on aerating it occasionally by forcing rods through it. I plan on adding kitchen scraps once it starts to heat up.
Does this sound ok?

Reply

rockie May 31, 2012 at 8:56 pm

Oh, and I’m watering each layer.

Reply

Steve June 1, 2012 at 10:00 am

@rockie, Yes, that sounds like a good plan, and no straw is not necessary, if you have some then add it but it’s not necessary if it’s costing you. Remember the majority of your material should be browns, so take it easy on the manure. A ratio of 3 to 1 should be adequate, by weight not volume.

Reply

rockie June 1, 2012 at 10:33 pm

woooops! I’ve already added 5 bags of manure. Hopefully that’s not too much. I go about 5-7 inches with browns then about 2-3 inches of green. I put a layer of straw on top of my grass clippings then add a bag of manure on top of the straw. I then start that process over again. I’m going to add one more layer so that I’m at about 3 and a half feet high. Does it matter what I end up with as far as browns or greens? I was thinking I should end with browns so that I can start adding kitchen scraps once the pile starts to cook.
Also, should I put a tarp to cover up the sides since its chicken wire and the pile is exposed to the sun and wind?
Thoughts?

Reply

Steve June 4, 2012 at 9:42 am

@rockie, You should end with browns, i.e. carbon. But keep in mind you should be mixing it, so end the end it will be mixed regardless. Yes, covering the sides and top is a good idea, keeps it moist and hot.

Reply

Leave a Comment