Sometimes, I question the decision to teach my four-year-old how to compost. Like when he spent 10 minutes today ripping up a tiny piece of newspaper to add to it. Or touched the composter after I turned it and it was dripping with decomposing goo. Thankfully, he didn’t put his hands in his mouth. At least not this time.

Despite the gross moments, composting with kids is worth it. As a way to reduce waste and save money, it’s a worthwhile skill in and of itself. It’s also a pathway into so many other lessons in ecology, food waste, and biological cycles.

A landfill is the worst possible environment for decomposition to occur. Because landfills don’t have oxygen, food waste can’t break down properly. It releases methane, a nasty pollutant and greenhouse gas that’s 84 times stronger than carbon dioxide in terms of its short-term contribution to climate change.

In contrast, composting mimics how biological materials decompose in nature. In forests, under the ground, and pretty much everywhere else, bacteria, fungi, and small animals break down dead matter and turning it into soil. By providing the perfect environment for that to occur, composting just makes the process go faster.

If you don’t have any way to compost outside, many cities now have businesses that will collect and process your food waste for you, like Compost Cab in the greater D.C. region.

Materials you need for composting with kids

If you’re only composting yard waste, you can use a simple mesh composter, which is just a rectangle of plastic or metal mesh open on the top. Composting yard waste just requires holding it in one area and providing space for air to circulate. If you want it to be as easy as possible and don’t mind being a bit messy, you can pile it all up in one corner of the yard.

If you want to compost food, an enclosed composter is a much better bet. These composters have locking lids, which are very helpful for keeping out raccoons, mice, rats, and other critters. A number of different types of varying sizes and price points can work, depending on your needs. If you have a bad back, I would strongly recommend a tumbling composter that advertises itself as easy to turn.

In addition, figure out how big a composter you need. If you don’t produce a lot of fruit and vegetable waste, you can probably go with a smaller one. If you’re going to compost both food and yard waste, you probably want to go with a larger one.

We have the original composter from EnviroCycle, which has excellent customer service. (Our latch broke after five years and they sent us a new one for free.)

Involve your kid in picking out the composter, which will get them more invested in the process. You can ask them their opinions on color and size. You can even build one yourself, a great DIY activity for a parent and kid to do together. I’ve done this project and the hardest part is finding a big barrel. We got ours from the local Coca-Cola bottling plant.

Sorting the Compost with Kids

For yard waste, nearly everything can go in the compost. In theory, eventually it will break down. In practice, it’s a bit more complicated. Wood takes longer than any other type of yard waste to break down, so limit it to a few small branches if you do put it in. Most experts recommend not putting in weeds because weed seeds can survive very high temperatures that will destroy other plants. Potentially, weeds could grow out of the compost when you add it to your garden. Personally, we do it anyway and take the chance. Don’t add anything that has been treated with pesticides, herbicides, or fungicides, especially if you are going to use the compost in a vegetable garden.

For food, you have to be picky. We limit the food we put in our compost to coffee grounds, tea leaves, and fruit and vegetable waste with the occasional piece of stale bread thrown in. Some guidelines tell you not to put in certain types of fruits or vegetables (like citrus rinds) because they’re too acidic, but I think almost any produce is fine as long as it isn’t the majority of the compost. In contrast, never put in meat, eggs, dairy products, or items cooked with fat. These may attract animals and flies. They also don’t break down as quickly or thoroughly as produce.

Never put anything non-biological in the compost, including metal or plastic. Those items can last hundreds of years before they break down! Although some companies make “compostable” plastic goods, most of these will only break down in an industrial compost facility. Always check the packaging before throwing them in.

Sorting out the compost provides a good exercise for kids to identify different types of materials. When you throw something away, ask them if it should go in the compost, recycling, or garbage. It’s also an opportunity to talk about the problems with plastic and why we should limit how much of it we use.

To temporarily store your compost before bringing it outside, you can buy a fancy canister. Or if you’re a klutz who kept breaking the tops of their fancy containers like me, simply repurpose 32-oz yogurt containers. The Stonyfield Farms ones have excellent lids.

Maintaining the Compost

Once you have some compost, bring your kid, the compost, and some newspapers outside to dump it in the bin.

As you put the food in, throw in some shredded newspaper or other dry compostable material. To carry out decomposition, the bacteria and fungus need a balance of carbon and nitrogen as well as access to oxygen. If there’s too many food scraps (which are high in nitrogen) and not enough dry plant materials like leaves or newspapers (which have a lot of carbon), they produce sludge. Everyone needs a balanced diet, even bacteria! If the compost is too wet, they don’t have access to oxygen and suffocate.

For every 2-3 yogurt containers, I usually include a community newspaper or 1-2 sections of the Sunday paper. Shredding the newspaper is important to help it distribute evenly through the bin. Only use newspaper or office paper – glossy magazines have too many dyes and won’t break down well. Kids love helping with this step, considering their fondness for shredding.

Over the course of a few weeks, the process of composting will begin. You may feel some heat coming off of the compost, which is good. The bacteria are letting off heat as they work, just like people get hot when they exercise. Have your child hold their hand over the barrel to feel the heat. You may see some creepy crawlies inside, including worms, grubs, and beetles. That’s fine too! They’re part of the decomposition team.

There are a few tell-tale signs that something has gone bad. If you see large, gnarly flies, your compost is probably too wet. If it smells terrible – really reeks – your carbon / nitrogen ratio is probably off. In both cases, add a lot more newspaper and leaves. If it’s really bad, hold off on putting more food scraps in for a while.

Turn your compost about once a week. This ensures that all of the materials get to the middle, which is where the best composting action is happening. Tumbling it too often doesn’t give the microbes enough time to do their job.

If it’s a simple yard waste pile, you can do this with a shovel. For a tumbling composter, you need to spin it. (Other types of composters come with specialized directions on how to rotate or turn them.) While older kids can be helpful here, I would not involve little kids in this job. Turning the composter can be very heavy and messy. The watery goo drips out the bottom of the composter and then ends up coating the whole thing as you turn it. Considering how often my kid puts his hands in his mouth, I try to keep him from touching the liquid as much as possible.

Using Your Compost

Estimates on how long it takes material to decompose vary depending on what you put in, your climate, and your style of composter. I usually  wait six weeks between when I stop putting food in and when I use it in my garden. That gives enough time for the vast majority of food waste to break down. Waiting longer certainly won’t hurt. In fact, the longer you wait, the more likely you are to end up with good quality compost. If you plan on waiting a long period of time and want to still compost during that time, you can always get a second composter and switch off.

Once it’s ready to go, I find it easiest to dump it into a wheelbarrow. As you do this with your child, talk about how different it looks than the food and yard waste you put in. This is a good time to talk about the role of microbes and insects breaking it down into an entirely new material.

From there, just shovel it into your garden! You can apply it directly to plants that need a boost or mix into into the soil for an even distribution. If you want more activities with your kids, My Kids’ Adventures has a bunch of creative ones relating to composting.

Good luck composting with your kids!

For more on gardening with kids, check out How to Start Seeds for a Garden with Little Kids. If you want more resources and to talk to fellow green parents, be sure to check out my Green and Sustainable Parenting Facebook group!