Urban Garden Composting: Our Compost Tumbler Basics


This article is going to focus on how we started composting, and the factors we are considering as we work to expand and DIY our newest compost system. It’s my hope that you will follow our composting adventures and find system of composting that works for you.

So, what is compost and why did we want to start composting? Composting is a natural process where organic materials decay over time into a nutrient-dense soil amendment. We first opened our eyes to composting around the same time we started growing our own food. When you grow food, you really come to appreciate how much work goes into the whole process. 

One night I was chopping up some homegrown veggies for soup and I stared down at the chopped tops, ends, and damaged pieces and thought ‘I grew this and I don’t want to waste any of it!’ I think that was the moment composting really clicked for me. It was a way that my garden could feed itself.

You can take garden “scraps” and turn them into the most valuable garden amendment—compost!

How we started: Compost Tumblers

When we first decided to start composting, I was really nervous about the smell and critters. One theme you’ll see over and over on this website is “urban gardening.” We live in a residential neighborhood with squirrels, opossums, rats, raccoons, cats, and more. I also believe in being a courteous neighbor and would have been mortified if our neighbors complained of smells. For these reasons, we decided on a compost tumbler—a fully enclosed bin that you manually turn/rotate every few days.

Our decision became a reality when we got our hands on a tumbler that an experienced gardener was giving away because they no longer needed it. Honestly, getting this tumbler was a blessing in more ways than one. First, it saved us money. Second, it really forced us to stop feeling unsure and just get started composting. Third, it demonstrated that you don’t need to overthink your tumbler choice. This wasn’t the most popular or up-to-date tumbler model, but it has created amazing compost for us over the years. Just get started! You can see our tumbler along with another interesting model HERE.

Some Compost Tumbler Basics

»You can turn/rotate your bin as often as you would like. When we first got our tumbler, I felt as excited as when gardeners start seeds. I went outside every morning and turned it just for fun—because it felt like I was “composting.” Does that sound silly? Ideally, turning every day or every couple days can facilitate better airflow and make the process go faster, but I never feel that this process needs to be about speed. Turn it once a week or as often as you remember. Either way, it will breakdown, as long as you have the ratio of browns to greens correct.

»Have a good ratio of brown materials to green materials (1:1). Brown materials are carbon inputs—such as cardboard, dead leaves, wood chips, compostable coffee filters, shredded paper, and wood shavings. Green materials are your nitrogen inputs—such as grass clippings, fruit and vegetable scraps, washed egg shells, and coffee grounds. While there are some differing opinions on the ideal ratio of browns to greens, we personally like to add 50 percent browns and 50 percent greens. 

»You don’t need to worry about temperature. Tumbler composting isn’t necessarily “hot composting.” It actually takes a pretty large mass of materials to create a compost pile that is steaming hot, so compost tumbling is more like a version of cold composting. There are benefits to hot composting—reaching temperatures as high as 140 degrees F can enable you to kill weed seeds and pathogens—but since compost tumblers work at cooler temperatures, you should be wary of adding things that might sprout, be invasive, or diseased plants/cuttings.

»Can the tumbler be difficult to turn? Absolutely. I always like to say this because I was originally surprised by how difficult it was to turn our composter when full. It usually takes two hands and pretty good force—but I consider it part of my workout.

Get the compost started

The picture above shows an entire batch of compost from our single compost tumbler. This particular batch is NOT DONE. It is being finished in these tubs because we needed the space in our tumbler. As you can see, compost tumblers can generate quite a large amount of compost, so if you are a small space gardener, they could be a wonderful option for you. Also, if you were able to get your hands on multiple tumblers, that would be a great way to expand your system without having to worry about animals or smells.

Add as much of the browns and greens you have accumulated (don’t worry, it doesn’t have to be completely full to start) and give the compost tumbler a few good rotations to mix it up. Usually there’s enough moisture to start because of your greens.

NOTE: I do like to chop up my vegetable/fruit scraps, sticks, and shred any paper. Smaller pieces breakdown more quickly in general, but compost tumblers seem to perform better overall when the pieces are smaller. That being said, I don’t get crazy with it. I like varying sizes in my organic materials because it allows for better aeration and less matteing.

Continue to rotate every few days (or as much as you’d prefer).

Watch for moisture levels. A certain amount of water is needed for the decomposition process to happen. Ideally, you want your compost to be the texture of a wrung out sponge BUT I think it is better to have a drier pile than an overly wet pile. Add water if needed.

Keep on adding material until the tumbler is mostly full. This part can be tricky. Unfortunately, one drawback of a tumbler system is you might have materials all decomposing at different rates because you are adding new material over time to the same compartment. This simply means that your compost won’t be ready to use until those very last added items have completely broken down. That is one reason why having more than one tumbler can be beneficial—one tumbler can be finishing while you are adding new materials to the other tumbler. They do have some tumblers available these days that have two compartments from this purpose, but I have not tried them.

See the graphic below with some examples of browns and greens. Avoid adding any glossy or extremely colored inked paper to your compost pile because of the chemicals used to create them.

My Best Compost Tumbling Advice

»Don’t become obsessed with speed and efficiency. Yes, there are ways to make the process happen faster, but start by observing the process of how organic materials break down into dirt. I used to feel overwhelmed by all the tips and tricks for composting—but I can tell you I’ve ignored my tumbler for months and months before and everything still broke down just fine.

»Take note of the smell. Compost does not smell bad. It smells earthy—almost like mulch. If your compost smells bad, it means that something is wrong. For example, a strong ammonia smell means that you most likely have too much green material in your bin. Simply add more brown material, rotate, and check back in a day or two.

»Urban composting comes with its own set of challenges. We don’t always have access to lots of brown material (dried leaves, etc.) and we have neighbors and critters to worry about. Most importantly, for beginners and urban dwellers, don’t get too adventurous with what you can add to your compost. I’m pretty selective, mostly for smell and sanitation reasons. Remember, compost tumblers don’t get very hot…so it’s hard to kill pathogens properly. DO NOT compost meat, animal waste, dairy, leftovers, or anything else that could be potentially hazardous or smelly. Also, DO NOT compost diseased plants. There is a chance the pathgen won’t be killed and canbe spread to your garden. 

When is compost finished?

Due to the many factors involved in the decomposition process, I can’t really give you a time frame for when your compost will be finished. My best advice is to go by look, feel, and smell.

Finished compost will look like a rich amendment. It will be dark and crumbly, and none of the components should be recognizable (meaning you shouldn’t be able to identify any of the items you added).

It should feel like moist soil and not have large pieces leftover. If you do see some large pieces, but the rest looks completely done, you can simply remove them and save them for the next load.

Finished compost should smell earthy.

Considerations for our new compost system

Fast forward to my garden goal for 2020: get better at composting! After seeing how much compost benefited our garden, I knew I wanted to expand our system and make enough to supply our entire yard! Another huge motivating factor was realizing how much money we were spending on bags of compost to cover our whole garden each season. As we made plans to design and expand our composting system, here were the top concerns from our urban garden perspective:

Space. The only area we have available for composting is our side yard. Not only do you need space for your compost, but you also need space to operate a shovel or garden fork. It would be really difficult to turn a compost pile in a thin alley or side yard.

Critters. The last thing you want as an urban gardener is to attract rodents to your space. I didn’t want rats or raccoons seeing our compost bins and coming over for a late night snack. We needed them to be enclosed enough that there would be no way for animals to access the food scraps inside.

Climate. Composting in a hot environment. California is a desert. Our hottest temperature in the Summer is about 112 Degrees F. This does actually influence your compost pile! In addition to being very dry (little rain), the heat also can increase the evaporation of any moisture we have. Therefore, we knew we wanted a cover for our bins to stop moisture from escaping, and we chose a location that is partly shaded.

Airflow. One benefit of tumblers in a dry, desert environment is the retention of water. It’s completely enclosed, so the compost getting too dry is not really a concern. With a larger system, you still want a good amount of oxygen to be able to penetrate the larger mass of organic material, so ventilated sides is a great way to do that.

What will happen to the compost tumbler?

I have decided to incorporate the tumbler into our composting system as a “processing bin” of sorts. I’d like to toss new kitchen scraps into the tumbler, along with some browns, and pre-process that kitchen waste before transferring it to the pallet bins. My hope is that this will truly eliminate any concern that critters would be attracted to our bins.

There are many options when it comes to compost systems, but I hope that reading about our thoughts and plans will help you make decisions for your space as well. You can find many of the items that we will be using in our compost system on our Garden Supplies & DIY Amazon List.

You can now read the next installment of my beginner composting series: An Urban Pallet Compost Bin Design

⇓ Are you planning to start composting? What are some of your composting questions or experiences?⇓

PS: Tag me in your garden photos with #FreckledCA on Instagram!

Meet Randi

Urban gardening is my jam. I’m Randi, California girl who obsessively gardens to grow food and flowers around my urban home. Seasonal, simple living is what inspires me~ I hope it will inspire you too. Join me in crafting a life and home connected to the garden Read More>>>>

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