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Tips for indoor composting

How to compost indoors

Composting indoors is a great way to eliminate some of your kitchen waste. It's an excellent alternative to outdoor composting for those without a garden or anyone who simply doesn't need enough compost to justify maintaining a sizable outdoor compost heap. 

Although indoor composting is relatively simple once you know how, getting started can seem overwhelming. We compiled a range of tips on indoor composting to help you out, from getting started to troubleshooting problems you're experiencing with your compost. 

What to put in your indoor compost bin

Before you get started, you should know what you can and can't put in your compost bin. The items you put in a composter fit into two categories: green matter and brown matter. Additionally, there are some types of kitchen scraps that aren't suitable for composting. 

Green matter 

Green matter is food and garden waste. It might not all be green in color, but it should be plant-based. Green matter includes fruit and vegetable peels and scraps (excluding citrus fruits), coffee grounds, tea leaves, healthy plants and cooked or uncooked grains, including bread (though only in moderation). 

Brown matter

Brown matter is carbon-rich material that's also essential for making compost. This includes cardboard, newspaper, paper towels, coffee filters, dry leaves, sawdust, pet fur and human hair.

What not to put in your compost bin

Never put any meat or dairy products in your compost bin because these will make it smell bad and may attract rodents to your house. Also, avoid composting fats and oils, as these will turn rancid.

How to compost indoors

Follow these simple steps to get started composting indoors. You don't need much, but you should have everything in hand before you begin. 

Find your compost container

First off, you'll need a container to compost in. Small households of one or two can get by with a 5-gallon container, but larger households and those with a lot of kitchen and garden waste to compost should look for a 10- to 20-gallon container. 

The easiest option is to buy a dedicated composter, but if you can't find an appropriate option, you can buy a large lidded container and drill some holes around the top for ventilation.  

Start with brown matter

Begin by filling your composter around three-quarters full with dampened brown matter (the level will reduce when it starts compacting and composting, so you'll have space to add more green matter). See the section in brown matter above to give yourself some ideas of what to use. Any cardboard pieces should be shredded, though you can simply ball up sheets or paper or paper towels. 

Add soil

Sprinkle around a cup or so of soil on top of your brown matter. Experts are divided on this — some say soil contains bacteria that help get the composting process started, while others believe adding soil isn't necessary. Ultimately, the soil can't hurt your compost, just make sure it’s not overly wet. If you think your compost is too wet, add some absorbent dry matter, such as sawdust, paper or cardboard. 

Common indoor composting concerns

My compost is moldy

Mold is perfectly normal in a compost pile, so don't be alarmed if you see mold. You can, however, make sure it isn't excessively wet. 

Some substances aren't composing

If you notice that some kitchen or garden waste pieces aren't breaking down, your compost pile may be too dry or lacking aeration. To improve aeration, turn your compost regularly. To make it less dry, simply add a little water. 

My compost smells like ammonia

This is a sign that there isn't enough carbon in your compost. It's an easy fix — just add more brown matter, like dried leaves or paper. 

My compost smells like vinegar or rotten eggs

A vinegary or sulfuric rotten egg smell usually means that the pile is either too wet, too compacted or not aerated enough. Turn the compost to improve aeration and reduce compaction, and add brown matter if it seems too wet. 

What you need to buy for indoor composting

SCD Probiotics All Seasons Indoor Composter

This compact 5-gallon compost bin is perfect for small households without a huge deal of kitchen waste. It's simple to use and comes with a probiotic compost accelerator. 

Where to buy: Sold by Amazon

FCMP Outdoor Half Size Plastic Rolling Composter

Although technically designed for outdoor use, this composter is compact enough for most kitchens. The 19-gallon capacity is ideal for larger households and those serious about composting.

Where to buy: Sold by Home Depot and Amazon

Ames Ergo Gel Grip Hand Trowel Transplanter

This handy little trowel is useful for burying new straps and turning your compost. The gel grip handle makes it comfortable to use

Where to buy: Sold by Home Depot and Amazon

Lauren Corona is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money.

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