I Tried This High-Tech Composting Service, and Here’s My Honest Review

published Jul 27, 2023
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Someone putting food scraps into Mill compost bin.
Credit: Courtesy of Mill

There are so many reasons to get on the composting bandwagon. Composting reduces food waste, keeps organic material out of landfills (where it produces methane emissions that are harmful to the environment), and can replace artificial fertilizers in your garden. And if you’re a gardener with the space and dedication to tend to your own compost pile, the results are one of the best ways to enrich your soil (and grow happy, healthy plants). 

But composting does have some unpleasant downsides. Common complaints include the smell of rotting food (a real negative if your food scraps bin is in your kitchen), as well as the attraction of pests like fruit flies or worse. (One solution is to keep scraps in the freezer, but if you’re cooking often, the freezer can fill up pretty quickly, if you even have the freezer space in the first place.)

The other challenge, if you aren’t composting yourself — a satisfying process, but not one without the investment of time and elbow grease — can be getting your scraps to a place where they can be made into compost. (Compost is the product of microorganisms breaking down organic matter. The food scraps from your kitchen provide the “fuel” for this process, but are not the final product.) Depending on where you live, some municipalities offer curbside organics collection, but many don’t. Local community gardens or environmental nonprofits may accept them for composting purposes, which requires transporting your food scraps (read: more time and elbow grease).

The upshot: Composting is great, but can be hard to make happen.

Which is why I was super excited to try Mill, a new subscription service that makes composting easy, simple, and even kinda cool. 

The Mill service consists of the Mill kitchen bin itself, a sleek appliance resembling a standard kitchen garbage bin; an app for remote control, information, and service requests; and the collection of your “food grounds” at the schedule of your choosing. With the reduction of food waste at the core of the company’s mission, Mill works to use food grounds as an ingredient in safe, regulated, and nutritious chicken feed, therefore keeping consumers’ food scraps in the food system. 

Customers can choose between a monthly or annual service plan. The cost of the annual plan is $33/month, billed annually at $396. For the monthly plan, customers are billed $45/month, plus a one-time $75 bin delivery fee.

The people at Mill offered me the chance to try a kitchen bin out for a month. Here’s how it went. 

My Mill arrived in a big, hefty box. I was somewhat surprised at the size (50 pounds!), but it was extremely well-packed, and the bin came out of the box fairly easily. Setup was quick and simple —  while it isn’t tiny, it’s not an eyesore — it was designed by alums of Nest and Apple, and it shows. I don’t have a super-small kitchen, but I don’t have a big one either, and I didn’t mind the Mill’s footprint. 

Credit: Mimi O'Connor

We cook a lot in our house (and are guilty of finding mold-engulfed fruit in the fridge from time to time), so we had plenty of scraps to add to our Mill from day one. It’s super easy to use: You step on the pedal at its base, dump them in, and close the lid, just like a standard kitchen trash can. One cool thing about the Mill is that you can add almost anything to it, thanks to the 2000 pounds of force behind the device’s metal grinding paddles. Mango pits, avocado pits, and bones are all fair game, as is meat. 

If a user ever has any doubt, the Mill app is a great resource for finding out if an item is Mill-appropriate or not. The two big things that should not go in a Mill are compostable plastics — because it’s not food — and liquids. One of the key functions of the Mill is to dehydrate food scraps, so adding liquids slows down that process and decreases the unit’s efficiency.

Credit: Mimi O'Connor

The time it takes your Mill to “process” your food scraps will range depending on how much you put in, the moisture content, and a few other factors, but it takes several hours. A run-time of five or six hours was common for ours. (You can set the Mill to run whenever you want, and overnight made the most sense for us.) 

When the Mill is doing its thing and grinding up the food scraps, it locks (a display will reflect this) and additional lights indicate that the magic is happening. It also emits a barely-there hum during this process. 

A low beep indicates when the Mill is done. Lift the lid, and those food scraps have been transformed into dry, brown, lightweight, odorless granules that look and feel similar to coffee grounds mixed with dirt and sawdust. (Hence the term “food grounds.” Gross factor is pretty much zero.)

Credit: Mimi O'Connor

I spoke to the folks at Mill before giving one a try. They told me Mill would reduce the size of my food scraps by as much as 80 percent. And because of this, it could take two or more weeks to fill my Mill’s internal bin to the level that it should be emptied. They also said my kitchen trash bag would be lighter due to the lack of heavy food scraps in it, and that I’d probably take out the trash fewer times. What can I say? All true. 

The thing that I most appreciated about Mill was how clean it made the “disposal” of our kitchen scraps, but it was its seemingly infinite capacity that truly amazed me. We made dozens of salads, omelets, bowls, and more, and even after a month, our bin still wasn’t to max capacity. Another plus is that Mill provides free charcoal filter replacements if you need them.

The next step, which I was most worried about, was arranging pickup for the grounds — which couldn’t have been easier. I hopped over to the “Send it” section of the app, and requested a pickup for the next day. Mill provides the bag, the box, and shipping, and you can also bring your box to a dropoff location, which includes post offices, if you’d prefer that. Do you have an organics collection in your town? You can drop your Mill grounds in curbside collection bins as well. Then, it heads to their processing facility where it becomes chicken feed. In the app, you can see directly your impact on the environment with every batch of grounds sent, detailing feed production, landfill and greenhouse gas emissions avoided, and more. 

While Mill says you can add the grounds directly to your garden if you want, they aren’t technically compost (which takes months to create), and might not create the desired effect — and by sending them your food grounds, you keep the food in the food system. 

The TL;DR: I loved Mill. It made composting — or more accurately, prepping food scraps for composting — simple, easy, enjoyable, and even fascinating. It’s amazing, but not cheap. If you want to compost but hate the mess, generate a large amount of food scraps in your home, are passionate about caring for the environment and reducing food waste (or all of the above!), it could be worth finding the funds in your budget to have your very own Mill.