Yes, you can compost in winter.

Your pile doesn’t need to hibernate. You don’t need to stop collecting food scraps. And no, you don’t need some fancy heated bin or expensive equipment.

I run a community compost operation here in NYC, which means I can’t take winter off or allow my scraps just to pile up and freeze.

Every month, 200+ pounds of food scraps flow into our bin from neighbors. If my system stops working in January, I have an overflowing disaster, disappointed composters, a bad look for the community composting movement, which I often argue deserves more investment.

So I’ve figured out how to keep things cooking through everything else New York winters throw at us.

Winter composting isn’t fundamentally different from summer composting. The biological process is the same. The materials are the same. The end result is the same beautiful, dark, crumbly compost. But some parts of the job get harder. (If there’s a consolation, other parts are easier in winter.)

If there’s already snow on your pile and it’s gone cold: Don’t worry. We’ll talk about how to bring your pile back to life.

To Summarize: Your Winter Compost Checklist

• Your pile has to be big. More volume means more heat generation and better heat retention.
• On the ground and insulated is better. This also helps keep the heat in.
• Chop up the scraps more. Speeds up decomposition and the microbes doing their thing.
• Check the temperature. You’ll want to know if it’s active or not.
• If it’s under 100° F, don’t mix it. The trade-off of losing heat isn’t worth it. Exception: if it’s warm (40° F+) outside
• If it’s under 100° F, add extra greens. You need an injection of nitrogen.
• If it’s over 130° F, then proceed as if it weren’t winter. Mix it and add browns.

Winter Composting Principles

Okay, let’s get into it.

1) Make Sure Your Compost Pile is Large

This is the single most important thing you can do to keep your compost active through winter.

Aim for a minimum of 3 feet × 3 feet × 3 feet. This isn’t an exact science. If you’re in a milder winter, you can get away with smaller, and vice versa. But this is a good baseline.

Bigger is better if you have the space. The larger the mass, the more heat it generates and retains. It’s like the difference between a campfire and a bonfire.

Why Does Size Matter So Much?

This is a question of physics. It’s not actually the total size, but the surface-area-to-volume ratio.

A large pile has more volume (where heat is generated by microbial activity) relative to its surface area (where heat escapes to the cold air). The core of a big pile stays insulated by all the material around it. This is also why one big ice cube, like in a glass of whiskey, takes longer to melt than lots of smaller ice cubes.

Piles with lots of exposed surface area lose heat too quickly.

A larger pile also generates more heat to begin with. More material means more microbes, more decomposition. It’s why the most extreme examples of composting, like using it to heat greenhouses or get hot water, have giant piles.

How Do You Make Your Pile Large Enough?

Obviously, you just gotta add more material. But I’ll share my process.

In late summer or early September, I harvest as much finished compost as I can.

My logic for this is that it gives us October and November to build volume back up before the real cold hits. When it does, we have a big pile with more materials already undergoing the decomposition process.

Early fall is also a great time to spread compost, so it works out on that front too.

If you have multiple piles going, winter is the time to consolidate. You can separate them again in the spring.

Space vs. Size: How I Deal with a Slowing Down Pile

The tricky part about this for me is the balancing act between space and size.

My bin isn’t that big, so things slow down in cold weather, even in an active pile. That means you need some extra space so you’re not overflowing every week. But if you have too much empty space, your pile never builds the mass it needs, and it slows down even more. It’s a bit of a Goldilocks situation.

So I aim to have my bin about 70-80% full heading into December. That gives me room for another month or two of additions while maintaining a large enough pile to stay hot. If I’m running a hot pile, I know I can add more because it’s processing quickly.

2) Chop Everything Smaller

Hardcore composters always mix their greens and browns together and chop them into bits before adding them to their pile.

The smaller you chop your materials, the easier it is for the microbes to do their thing. Smaller bits = more surface area for microbes. That means faster breakdown, which means more heat generation, which means a pile that stays active through the cold.

This is more important in the winter because you have less margin for error. In July, I can toss in a whole coconut shell in. The warmth and active microbial population can handle it. In January, that same coconut, even if my pile is active, is going to be like a frozen brick that’ll sit there until March while taking up valuable space and contributing nothing to your pile’s heat.

My Chopping Process

1. I mix a 2:1 (or 3:1) ratio of browns like dead leaves to food scraps in a 5-gallon bucket. When browns touch greens, it also makes sure it’s not too wet and that oxygen can move through
2. I use a garden spade to chop it all up and mix it.
3. I dump the bucket chopped up scraps into my bin.

What Stays Out of My Winter Pile (Limited Quantities Only)

By November, there are some items that are just going to have to wait until spring. If it won’t attract critters, I keep these in a lawn bag.

• Coconut shells from the Dominican street vendor. They’ll sit in a lawn bag.
• Sticks, twigs, or other hardy yard waste.
• Avocado pits. (Don’t tell my girlfriend, but I collect them in our apartment until spring).
• Too many bones. I’ll keep them in our freezer if there’s space.

Yes, chopping takes more time. Yes, it’s annoying when your hands are cold. But it’s the difference between a pile that stays at 110°F and one that drops to 60°F.

3) Insulate The Bin

Insulation works both ways in composting. It keeps heat in during winter and prevents your pile from overheating in summer.

Some bins can provide some insulation. Wood bins probably have the most. Plastic bins like mine may have some, but not as much (but dark plastic can help absorb solar heat.)

Mesh bins or open piles have essentially zero insulation.

Adding Insulation: The Easy Method

Every time I add materials to my pile in winter, I cap it with a 3-4 inch layer of hay. Hay is used for animal bedding for a reason.

How do I get it? Often, events for Halloween use hay, and around the neighborhood I go collect it for the winter.

Hay is also a great compostable material. Over time, the microbes will have their way with it.

Tarps?

Some composters swear by covering their bins with tarps in winter. I’ve never done this, but the theory is sound if the sun hits it, creating a slight greenhouse effect.

If you use a tarp, make sure there are gaps for air circulation.

Location Matters Too

If you’re setting up a new bin or have the flexibility to move yours, put it in the sunniest spot possible. South-facing in the Northern Hemisphere, where it’ll catch maximum winter sun.

Also consider wind protection. If your pile is getting blasted by northern winds, it’s losing heat constantly.

The combination of a good bin, a topper layer of dry carbon, and smart location can keep your pile 20-30°F warmer than an uninsulated pile in the same conditions. That’s often the difference between active and dormant.

4) Check The Temperature More Often

In summer, I’m casual about temperature. I can tell my pile is active by smell, by how fast materials disappear, and by the general vibes. I check it because it might be too hot.

In winter, I check the temperature more. It’s your primary diagnostic tool for pile health.

The best and most serious composters are always checking the temperature. (Not me, but I’m better about it when I need to be.)

In summer, composting happens almost no matter what you do. The ambient warmth, active microbial populations, and longer days all work in your favor.

How to Check Temperature

Push the thermometer into the center of the pile, at least 12 inches deep. The center is where the action happens.

I check it once a week when I do my mixing.

I highly recommend a compost thermometer, the kind with a long probe (at least 12-18 inches) and a dial or digital readout. You can buy them, but many cities or towns that are supportive of composting and know its value, have them available. Find the compost people in your area and see if they’ll give you one, especially if you community compost. Along with our bin, we got our thermometer for free from the New York Botanical Garden.

What Temperatures You’re Looking For

These are frameworks. They’re not perfect. People will debate them. But this is what I work off of, and it’s the general range that really matters.

• 100-130°F: Sweet spot. Your pile is actively composting. Keep doing what you’re doing.
• 90-100°F: Still active. For winter, this is a success, but we can do even better.
• Below 90°F: Getting cold. Time to intervene with greens and stop mixing.
• Above 130°F: Very hot. Throw out my winter tips. You need to mix it to prevent it from going anaerobic and add more browns. Above 130, good microbes start to die. This is useful in some situations, like killing weeds, but for food scraps, it’s not necessary.

In summer, I’m worried about oxygen and smells. I’m mixing weekly and trying to keep things aerobic. But in winter, I want to know exactly how hot the pile is because that dictates my entire management strategy.

5) If Your Bin is Less Than 100° F (38° C), Add More Nitrogen (Greens)

Nitrogen is always the fuel that drives composting activity. Just like humans, microbes use nitrogen to make proteins and enzymes.

Without enough nitrogen, the microbes can’t reproduce quickly, can’t work efficiently, and won’t generate the metabolic activity they need to survive.

If my pile is under 100° F, the fastest way to get it cooking is to add a surplus of nitrogen.

Easy, High-Volume Nitrogen Sources

If you’re just adding to your pile as you collect food scraps, it’ll take time. But to speed it up, look for ways to inject some nitrogen.

• Coffee grounds. These are crack for your pile. I’ve seen a 20°F jump within a few days of adding a bucket of coffee grounds. At our garden, we have a good relationship with a coffee shop around the corner. If we need more nitrogen, we ask them, and we’ll have at least a 5-gallon bucket’s worth. Go ask your nearest coffee shop.
• Juice or fruit shops. Like coffee shops, juice or fruit shops will have lots of nitrogen for you.
• Urine. Yes, I pee on my pile. Before you think I’m nuts, urine is basically sterile, high in nitrogen, and has been used as a composting accelerant for centuries. No, I don’t do it in front of people. The logistics of this are the topic of another day. If my pile is too cool, I pee on it.
• Fresh grass clippings. Tougher in the winter, but if you can find them, they’ll also speed things up fast.

Don’t Abandon Browns Entirely

Even when you’re focused on adding nitrogen, you still need to add some browns (carbon). I still throw in fall leaves.

In summer or when my pile is running hot, I aim for about 3:1 browns to greens by volume. But when my winter pile is running cool, under 100°F, I might shift to 1:1 or even 2:1 greens to browns.

Once your pile climbs back over 100°F and stabilizes there, return to your normal ratio, around 2:1 or 3:1 carbon to nitrogen. If it climbs over 130°F, you’ve gone too far. Add more browns and mix more to maintain aerobic conditions.

Monitor and Adjust

I know I said to check your temperature once a week. If you’re in the midst of winter compost CPR, it’s better to check every few days. When you check the temperature frequently, you’ll start to get an intuitive feel for the right ratios of greens to browns and how it impacts your pile.

6) If Your Bin is Less Than 100° F, Don’t Mix The Pile

This one may be controversial. Other composters may feel differently. And for good reason.

In summer, I mix my pile every week, sometimes more. Mixing is crucial because it introduces oxygen, which keeps the decomposition aerobic (good) rather than anaerobic (bad).

Aerobic decomposition produces heat and beautiful finished compost. Anaerobic decomposition produces methane (a potent greenhouse gas), terrible smells, and slimy, poor-quality results.

But in winter, the rules change.

Why I Mix Less In The Winter

Yes, oxygen is still important. Your microbes still need it. But when your pile is barely holding at 95°F, and it’s 15°F outside, mixing it means introducing freezing air directly into the core of your pile. You’re opening the door of a warm house in January.

That cold air will drop your pile’s temperature.

So here’s my framework: base your mixing decision on temperature.

• Below 100°F: Don’t mix. Your priority is keeping whatever heat you have trapped inside. An unmixed pile might get slightly less oxygen, but a cold pile will go completely dormant. Choose warmth.
• 100-130°F: Mix less, but regularly. Maybe every 2-3 weeks instead of weekly. Do it on the warmest part of the day if possible.
• Above 130°F: Mix it. At this temperature, your pile is running so hot that going anaerobic is a bigger risk than losing some heat. Plus, a pile this hot will recover temperature quickly after mixing.

Exception: Turn Your Pile on On Warm Winter Days

New York has cold winter days, but also has warm winter days. On warm days is your chance to get the benefits of mixing with less risk. So if it’s 40°F and sunny, I will turn my pile and give it some fresh oxygen. The fresh oxygen means the microbes can breathe, and can help speed up their activity and heat up your pile. But in my experience, the exposure to freezing temperatures cools off my pile.

7) When Spring Comes, Add Extra Browns

If you’re doing things perfect this isn’t necessary, but it has been necessary for me because I’m not perfect. In my quest to make sure there’s enough nitrogen, often when spring comes, my bin gets too hot and goes anaerobic. When winter starts to break, I start to add extra browns to this.

I’m talking more leaves than you think you need. You want to shift your ratio from that nitrogen-heavy winter mix (maybe 1:1 or 2:1 greens to browns) back toward a carbon-heavy spring mix (3:1 or even 4:1 browns to greens).

This does two things:

1. Balances out the excess nitrogen that’s been accumulating
2. Provides structure and oxygen pockets that prevent compaction and anaerobic conditions in an overactive pile.

Watch for Warning Signs

Your pile will tell you if you need to intervene:

• Temperature above 140°F: Definitely too hot. Add browns immediately and mix well.
• Strong ammonia smell: Sign of too much nitrogen and possible anaerobic conditions. Add browns.

Other Winter Composting Tips

More Sunlight is Better

My bin is not the best placed for this. It’s a community garden, so compromises are part of the deal. You can overcome it, but sun will help keep heat in during the winter.

Turn Your Pile When It’s Sunny and Warmer

I know I’m repeating this, but when you have a warmer day, ideally around 40°F (this will depend on where you live of course), that’s a good day to turn your pile, as you’ll get th oxygen benefits with less of the risks due to exposing the active microorganisms to cold weather.

For Moisture, Follow The Same Principles

The general rule is you want it to be moist, but not wet, “like a wrung out sponge.” In practice, for dry compost piles, you can add more wet greens (think banana peels), and that’ll take care of it. If it’s really dry, you can spray it with water. Covering with snow on top can actually provide some insulation and give it a drip of moisture.

If it’s too wet, oxygen won’t get in and it may start to smell.

How to Prepare for Winter Composting in The Fall

Here’s what I do in the fall to make winter composting easier.

Extract Finished Compost in September

In late summer or early September, I harvest as much finished compost as you can from your bin.

My logic is severalfold.

1. You need space to build volume in October-November. Those are your pile-building months. The bigger you can get your pile before December, the better it will perform all winter.
2. Fall is an excellent time to apply compost to garden beds anyway. September/October application gives the nutrients time to integrate into the soil before spring planting. You’re not wasting it—you’re using it at an ideal time.
3. Starting with a half-empty bin lets you build a uniform, well-mixed pile rather than adding to a pile that’s half-finished, half-fresh.

This helps me have a hot bin, ideally closer to 130°F, going into the winter too.

Gather Leaves, So You Have Enough Browns All Winter

When there’s snow on the ground or if it’s just cold out, you don’t want to have to go scavenging for browns.

In New York, lots of people sadly rake their leaves, but I can make the best of this by taking the bags of leaves that sadly might have gone to a landfill instead.

In my case, there’s an unlimited supply on the streets, but I take as much as we can store in the garden.

Winter vs Summer Compost: Pros and Cons

The summer requires more frequent work, but the winter requires more precise work.

Winter Composting: The Advantages

Smells are easier to manage. A pile that would reek in July barely smells at all in January.

Pests are dormant. No fruit flies. No ants. No hornets buzzing around. Rodents are less active (though not completely gone, especially in NYC). The pest pressure in winter is a fraction of what it is in summer.

Mixing is less frequent. In summer, I’m mixing weekly to prevent anaerobic conditions and manage smells. In winter, I mix 1-2 times a month.

You can see the heat. I love the satisfaction of watching steam rise from the compost pile.

Winter Composting: The Challenges

It requires more precision. You can’t just throw stuff in and hope for the best. You need to monitor temperature, adjust nitrogen/carbon ratios carefully, and make strategic decisions about when to mix and when to leave it alone.

Materials need more prep. Everything should be chopped smaller. You can’t be lazy about it the way you can in summer.

Temperature monitoring is essential. You need to check regularly and respond to what your thermometer tells you. In summer, you can compost successfully without ever checking temperature. Not so in winter.

It’s physically less pleasant. Going out to your bin in 15°F weather isn’t fun. Your hands get cold. Carrying materials through snow is annoying. The work itself is harder.

The margin for error is smaller. In summer, a pile can recover from mistakes quickly. In winter, if your pile goes cold, it’s genuinely difficult to get it going again.

Some materials have to wait. Tough items like corn cobs, avocado pits, and coconut shells won’t break down. You need to store them or throw them away.

Winter Composting FAQ

What Do I Do If My Pile Has Gone Completely Cold?

Okay, here’s the checklist.

• Size. Is it big enough? If it’s not, you need material. Get some coffee grounds.
• If it’s big, does it have enough nitrogen? If not, get some coffee grounds and pee on it.
• If it’s big and you added lots of nitrogen, insulate it.
• If that doesn’t work, get it in the sun.

If none of that works and it’s truly dormant, you can try mixing everything and keep trying to get more nitrogen-rich greens.

Can I Start a New Compost Pile in The Winter?

It’s not ideal, but you absolutely can. Follow the tips outlined here. Get as much volume as you can and focus on nitrogen.

Can I Winter Compost With a Tumbler?

Yes, but it’s not ideal. Tumblers can work for winter composting, but they have significant disadvantages compared to open bins.

• Most tumblers are too small. The typical 35-50-gallon tumbler doesn’t have the volume needed to generate and retain significant heat in winter.
• They lose heat faster. Tumblers are suspended in the air and have thin walls, meaning they’re exposed to cold air on all sides. There’s no ground contact to provide thermal stability, and no opportunity to insulate with soil or extra materials.

If you’re using a tumbler in winter:

• Fill it as full as possible to maximize volume
• Be aggressive with nitrogen additions
• Tumble it less frequently than in summer (only when the temperature is above 110°F)
• Consider wrapping it in an insulating blanket or moving it to a sheltered, sunny spot
• Accept that it will likely slow down significantly in deep winter

If you’re using a tumbler, you’re probably not processing serious volume anyway. Most tumbler users are single households composting their own scraps. If your tumbler slows down or goes dormant for January and February, it might not be a crisis. You can keep adding to it and accept that it’s not going to break down much until spring.

For serious winter composting, I’d strongly recommend a ground-contact bin of adequate size. But if a tumbler is what you have, you can make it work with the right approach.

Should I Cover My Compost Pile in the Winter?

It depends on your situation, but generally: a partial cover is helpful, a full seal is not.

Personally, I do a lazy cover by just throwing leaves on top. I would only cover my bin if other strategies didn’t work first.

How Do I Get Extra Nitrogen in the Winter?

Nitrogen is harder to come by in winter (no grass clippings, fewer fresh greens from gardens), so you need to be strategic about sourcing it.

Coffee shops are your best friend. This is the single best source of free, concentrated nitrogen in winter. Here’s how to make it happen.

The juice shop is your other best friend. Banana and orange peels are some of the best stuff.

I should probably write a whole article about this. Basically, you’ve gotta build a relationship with your nearby coffee shop.

Urine works. Yes, really. Human urine is roughly 11% nitrogen by weight and is essentially sterile when fresh. As I already mentioned, it’s been used as a composting accelerant for centuries. centuries.

Other winter nitrogen sources:

• Food scraps from your kitchen: Vegetable peels, fruit scraps, eggshells—save everything
• Ask neighbors to save scraps for you: Many people would love to compost but don’t. Offer to take their scraps.
• Manure: If you know anyone with chickens or rabbits, ask for their manure. It’s nitrogen-rich and available year-round.
• Spoiled produce from grocery stores: Some stores will give away produce that’s past its sell-by date. I’ve done this once with a nearby fruit stand. As long as you can transport it, it’s usually not an issue. I’ve had more lucky with mom-and-pop fruit stands than big grocery stores.

Can I Add Citrus and Onions in Winter?

Yes, absolutely.

Lemons and onions are acidic, but they break down just fine in a hot compost pile, and have nitrogen.

Like everything, chop it up and mix it well. Whole lemons are harder to break down than slices.

Should I Be Worried About Animals in My Compost Bin in Winter?

Fruit flies are dormant, but rats and maybe even raccoons may show up.

I’m in a city, so I don’t have to worry about bears, but I do have to worry about rats.

I do what I do in the summer. We have a rat-proof bin (topic for another day), and I always mix food scraps and bury the fresh stuff in the center.

I don’t think it’s any more of a concern in the winter than in the summer, but this may vary based on the type of environment you live in.

How Long Does Winter Composting Take?

Slower than summer, but not as slow as you’d think if you maintain an active pile.

I can only speak to experience here. Unless I need to take out finished compost because I’m out of space, I wait until March. But, I’ve had lots of finished compost started in December and finished three months later in March, with my pile active between 100-130°F all winter.

Should I Add Worms to My Winter Compost Pile?

One of the lazy composting strategies in warm weather is to get some red wiggler worms and add them to your bin. But if your pile isn’t already hot, they’ll die in the cold. Even in a warm pile, they’ll die if they get trapped near the cold edges.

I do not add worms to my pile, especially in winter.

Can I Start a Compost Pile in Winter?

Yes, but it’s harder than starting in spring or fall.

If you’re trying to, here’s what I would do.

1. Build big immediately. Don’t start small and grow. You need at least 3×3×3 feet right away. Find this critical mass from somewhere. A heap of grass clippings is ideal. With leaves, you can make it work, but you need nitrogen, so find a lot of coffee grounds or food scraps, fast.
2. Use a hot mix. Alternate layers of nitrogen-rich materials (food scraps, coffee grounds) with carbon materials (leaves, shredded paper). For the initial build, I’d aim for 1:1 greens to browns ratio for the initial build.
3. Add water. Your materials need to be moist (but not soaking) for microbial activity.
4. Insulate from day one. Top with thick layers of dry leaves. Protect from the wind.
5. Monitor temperature. Add more nitrogen if it’s not heating up.