Digging in the Dirt: 4 Home Composters Reviewed and Rated

Turn food scraps into compost for your garden with one of these indoor, odor-free devices.

I’m a big fan of composting, but it doesn’t always go according to plan. Recently, a rat moved into my compost pile. It seemed to have a particular fondness for coffee grounds. After several frank exchanges of views, I persuaded Colin the Compost Rat (as I christened him) to move on. That’s one of the occupational hazards of composting: A pile of rotting stuff is considered a delicacy by many creatures, and however well you protect and fence your mixture of kitchen scraps and garden trimmings, they will find a way in. While I celebrate all the fauna of the earth, I don’t necessarily want them living outside my bedroom window, especially when one of them is getting a caffeine buzz.

So, what’s the alternative to an outdoor, open-air compost pile? Home composting devices are one, simple machines that are meant to be used indoors, right there in the kitchen. A variety of devices exist to take your compostable waste and cook it down into a nutrient-rich, soil-like mix that you can dig into your flower bed. I tested some of these devices: the $300 Vitamix FoodCycler FC-50, the $499 Pela Lomi, the $429 BeyondGreen Kitchen Waste Composter, and the $429 Reencle Prime.

Composting Break Down

Before you can really decide whether one of these machines is for you, we should talk about what “compostable” really means. There are many products currently on the market—everything from disposable utensils to baby wipes—labeled as compostable. For a quick caffeine fix, I use Woken coffee pods, which the company describes as “100 percent compostable.” However, as Colin discovered, in a backyard compost pile the pods become a handy little lunch container because the exterior shell won’t break down for a long time. In its FAQ, Woken says its pods “turn into CO2, water, inorganic compounds, and biomass in municipal composting facilities.” That means they need industrial composting, which uses heat to break things down more aggressively than my pile of veggie leftovers, leaves, and rat poo.

So, can these home composters—all of which use heat and agitation to break down waste—turn a pile of food scraps and coffee pods into something useful? My top pick, the Reencle, produced a light, well-broken-down mix from pretty much anything I threw in it. All of the products struggled with tougher food waste, like banana skins and the coffee pods, often taking much longer to break these down.

In some cases, it might be better to leave your composting to the experts. As Joe Ray noted in his original review of the FoodCycler FC-50, if you have a municipal composting service, you can just throw the waste straight into the collection bins (and possibly get compost back from the agency for your trouble). If you don’t have access to a local composting service, making your own compost heap isn’t that hard, as long as you aren’t visited by Colin the Compost Rat. You could also pick up a barrel designed to process compost outdoors. But if you don’t have space or the desire for outdoor composting, these devices can produce compost from your everyday food waste and compostable stuff right there on your kitchen counter.


Best Overall

The Reencle Prime (Rating: 8/10, WIRED Recommends) tries to replicate processes from the natural world inside a container in your home. You set it up in your kitchen, put some water in the chamber, add the included Reencle Microbe mix, and then throw in the food waste. This tasty brew is quickly turned into a nutritious mix by fermentation. It is similar to the Bokashi process, which uses bacteria to break down food waste. The Reencle Plus works faster and more efficiently than Bokashi, though. Once the Reencle was up and running, most of my food scraps were broken down within a day, although tougher fibrous waste like banana skins and the Woken coffee pods took longer.

The ReencleMicrobe mix at the heart of this process contains rice husks, vermiculite, nonpathogenic bacillus bacteria, ammonium sulfate, and wood pellets, according to the company. You only add this once—as long as the device is turned on and gets fed occasional food waste, the bacteria responsible for breaking down waste will continue to breed and thrive inside the mix.

The device itself looks like a fancy trash bin, complete with an automatic lid that opens when you wave a foot in front of a sensor at the bottom. The lid closes automatically after a few seconds to seal the waste in. Buttons on the front turn the device on, dry the waste, purify it, and open the lid.

The idea here is that you put the food waste in continuously, and the mix digests it as it is added. So, rather than having to wait for a pile of stinky food waste to grow large enough to run the device (as with the Lomi and the FoodCycler, rated below), you throw scraps in when they are produced, and the Reencle runs continuously. The Reencle sucks air out of the digestion chamber and through a large carbon filter on the back of the device, so the aroma of decomposing matter doesn't leak out.

The company claims that the Reencle can handle up to 2.2 pounds of food waste a day when running properly. I found that it worked fine with differing loads: A big batch of veggie peelings on one day and a few coffee pods for the next couple of days didn’t phase it.

When the Reencle is full, you scoop out some of the processed waste, which comes out ready for you to dig straight into your vegetable patch. I found that this mix was always sufficiently broken down—only a few pieces of food and the odd bit of coffee pod were still intact, which probably wouldn’t encourage birds or other animals.

You don’t remove all of the mix. Some has to remain behind to provide enough bacteria to keep the process going. The device automatically warms, stirs, and occasionally dries the mix out to keep the microbes happy.

The Reencle can sit on the floor or a countertop.

Photograph: Reencle

It isn’t completely automatic. Sometimes when you open the lid to add more waste, you get a distinct whiff of rancid pickles from the fermenting action. This process can also go awry when the wrong bacteria starts to grow, which you’ll know about because it starts to smell worse. This can happen with too much food waste, or too much moisture in the mix. If this happens, Reencle recommends that you hit the dry button for a few days to dry the mix out. The purify button can also be used to pump air through the carbon filter, removing the odor.

The Reencle definitely works, but it shares the same problem I found with most of these devices: cost. The device is $439, but only if you preorder it now. The company is selling them through the crowdfunding platform Indiegogo, and current orders should ship in May. At some point in the future, the sale price will go up to the full cost of $699. That is a lot of cash to lay out, especially with more and more towns now offering bulk composting services. So, is it worth the investment? For city dwellers who are serious about composting, yes. Once it gets going, it works flawlessly. I’ve had one processing waste in my kitchen for several months without any problems or nasty smells. Still, the price is steep.

A Good, Cheaper Option for Most People

The new composter on the block is the Lomi by Pela (Rating: 7/10), a toaster-sized device that holds a bucket that can fit about one cubic foot of food waste. When you put the lid on and activate the Lomi, this bucket is heated, and a metal arm at the bottom stirs the waste and crushes larger bits, rather like a slow-motion blender. Meanwhile, warm air is wafted over the waste and pushed out through a pair of carbon filters.

Photograph: Pela

The Lomi has three modes: Lomi Preferred, Eco Express, and Grow. The Lomi Preferred mode is the best overall mode for handling a combination of food waste and bioplastics: It grinds and breaks down the waste over about eight hours. The Eco Express mode produces the same compost mix as the Preferred mode, but it does it over about 12 hours to save energy. The Grow mode is specifically designed for use with food waste only, taking about 12 hours to process the waste with the addition of water and a LomiPod, a bacteria-rich pod that helps break the food down. A handful of these pods are included with the Lomi, and more are available from Pela—though the price is still TBD at this moment.

I found that all of these modes did a good job, crunching the waste down into a light, even mixture that could be combined with soil to produce a nice mix for planting. The Lomi Preferred mode made short work of the Woken coffee pods, breaking them down so that only small chunks of the bioplastic cases remained intact. This mix was light and ready for use as soon as the cycle was finished.

An Even Cheaper Option

The OG of these devices is the Vitamix FoodCycler FC-50 (Rating: 7/10). We reviewed this food recycler before, but I am retesting it now so I can compare it to the newer products in this roundup. Vitamix's entry is about the size of a large bread-maker and looks similar; the twist-off lid reveals the lift-out bucket where you throw your compostables. This chamber holds about a cubic foot of food waste and comes with a changeable carbon filter in the lid. That’s good because the container can get kind of stinky if you leave it sitting around for a couple of days waiting to fill up. The idea is that you keep the container on your countertop, then move it into the FC-50 when it is full. Vitamix claims that you can throw in vegetable scraps, pet food, coffee grounds, and pretty much anything else produced while cooking (except oil and grease). Vitamix says that the key is variety: The best results come from a mix of types of waste, not just one.

The Vitamix guide gives conflicting info about adding in meat and bones, saying that they can be added in small amounts. Contradicting the company’s own advice, the manual says “Do not incorporate any dehydrated food waste (DFW)... that contains animal protein… into your soil,” which seems to rather defeat the purpose. Either way, I wouldn’t put meat and bones in this: The risk of Listeria and other nasty bacteria getting into your soil and your veggies is too high.

The removable food waste bucket can be kept within reach as you fill it, while the rest of the machine stays stashed out of view.

Photograph: Vitamix

Once the container is full and placed inside the device, you hit the start button and the FoodCycler does its thing, drying and grinding the waste down into smaller chunks over a four- to eight-hour period. A series of LED lights on top keep you posted, and the lid remains locked until the process is complete.

The result is a dry, crumbly mix that you can stir into soil and dig into your flower bed. I did find that it struggled to grind my compostable coffee pods. They were partly broken down at the end, but large chunks of the containers and other tougher food waste remained in the mix, which could attract animals like Colin. So, the final mix would benefit from being well dug into the soil, or left for further composting.

A More Natural Option

BeyondGreen Kitchen Waste Composter

The BeyondGreen Kitchen Waste Composter (Rating: 7/10) works a little differently from the rest. Rather than heating and dehydrating the mix, it heats and stirs everything in a sealed container surrounded by heat-resistant foam to encourage the natural bacteria to break the waste down. To get the process started, you add wood chips and a little baking soda (small amounts of both are included) to produce the right mix of what composters call the brown, the wood-like fibrous plant material, and the green, the growing plant matter that is food for the microbes. The Kitchen Waste Composter then heats and stirs this mix, encouraging the microbes to do their thing. This takes days rather than hours: Typically you won’t get finished compost out until at least seven days after it goes in.

The downside is that it gets a bit stinky. Although the foam cover that surrounds the device is well sealed, you have to open it to add more food waste, and you then get a face full of the smell, which is … well, food waste getting eaten by microbes. Think of a pile of rotting leaves. It’s not a pleasant smell, so this device is best put in a garage, basement, or other out-of-the-way place. Tougher waste such as banana skins and stringier vegetable parts may also need to be chopped up before dumping them in since this device stirs (rather than grinds) the waste.

Once the compost is ready, you hit the transfer button, and the compost is shoveled into a container at the bottom of the device, where you can easily remove it and add it to your soil. It produces a nice, well-mixed, and broken-down compost from most food waste, but you might still find chunks of food and larger bits in there. So, it should be heavily mixed, buried, or further composted to break it down further. I also found that our compostable coffee pods didn’t break down completely. I found chunks of the bioplastic casing still in the compost after a week. To avoid this, I had to crush and break down the coffee pods into smaller bits before putting them in.

More Great WIRED Stories