Composting is an easy, sustainable way to keep your garden healthy. In fact, a moderately sized, well tended bin can provide a nutrient-dense fertilizer for a good-sized garden. Many people get confused about what goes into a heap, and what doesn’t. Read on to learn what not to put in compost, and what to toss in there with great enthusiasm.
There are few things that can’t go into the compost bin. After all, composting is the best way to turn odds and ends from old salad greens, stale crusts, and rotten eggs into a rich growing medium. With just a little oversight, your compost bin will remain a healthy habitat for decomposition.
So, what shouldn’t go into the bin? Let’s take a look:
Meat and animal products like lard, broth, bones, and gristle should stay far from your compost bin. While blood and bone meal are excellent fertilizers, the home compost bin is not the place to make them.
These items stink while they decompose, which will attract unwanted animals. In essence, your bin will smell like a fast food restaurant to every dog, cat, rat, raccoon, and coyote in the neighborhood. Worse, it’ll smell like road kill to you and your neighbors.
Various animal products also take longer to compost than almost anything else. As such, they carry a huge risk of spreading disease to your garden if under-composted.
The best thing to do with leftover bones and meat is to make bone broth. Throw the rest of that roasted chicken in a pot and set it to simmer for hours. Strain out undesirable bits—I use a cheesecloth for this—and pack the broth away in your freezer. Then, throw the tiny, leftover meats scraps in the garbage.
Plastic, glass, aluminum, and other inorganic materials just clutter up your bin. Basically, they turn an otherwise thriving organic system into a landfill. Keep your compost bin free of unnecessary clutter by keeping these items out of there.
I have a bad habit of storing my compostables in tin cans, carrying them out to the bin, and leaving the can there to “air out”. Unfortunately, cans, jars, and bits of plastic won’t help your compost bin do its job.
They’re also potential hazards, since broken glass or sharp plastic stubs might mingle with your soil. Don’t fall into my bad habits. Instead, find a consistent compost container for your kitchen counter and use it to carry scraps out to your bin.
Human (and Carnivorous Pet) Waste.
Maybe you’ve heard of the humanure movement in composting? Even if you haven’t, don’t jump on the bandwagon! At least, not with your compost bin.
If you are going to compost human waste, research well and set up a separate location for that process. But, as someone who has relied on a simple composting outhouse for 8 years, trust me: you don’t want to use human waste in your garden.
Keep human and carnivorous animal waste out of the compost bin. Dog and cat feces can carry dangerous pathogens, which you don’t want to transfer to your edibles. In addition, their droppings aren’t as good for soil nourishment as chicken, goat, sheep, cow, rabbit, and horse manure.
If you have livestock, you can mingle manure into your compost bin. Chicken manure especially should be composted for a few months before being used in the garden. Horse, goat, and cow manure don’t need to composted, but can add a great nutrient boost to your soil.
These include used dish water, and half-empty bottles of disappointing shampoo. These may seem obvious to you, but I’ve been told by seasoned soil-building aficionados to dump them in. Don’t believe anyone who tells you to dump cleaners, detergents, or shampoos into your bin.
At worst, all these products will turn good soil into a sticky, soapy mess. At best, they’ll leave you with soapy-tasting tomatoes and sudsy soil.
Detergents don’t biodegrade well, and all the additives in cleaning products make them an unsafe addition to the bin.
This goes along with the human waste rule. Even if you’re using all-natural sanitary pads, tampons, diapers, and bandages, keep them out of the bin.
Not only is it just kind of gross to have them in your compost (and later on your garden), but hygiene products are likely to spread disease.
Bloody bandages, diapers, and feminine products are more likely to attract animals as well. If you’re hoping to keep your hygiene products out of landfills, try reusable options like cloth diapers, cloth pads, cotton bandages, and menstrual cups.
Garden extras like pea vines and carrot tops are perfect for the compost heap, but only if they’re healthy. If they’re diseased, keep them out.
Blighted plants may introduce disease into your heap. As such, it’s a good idea to burn them instead to keep the sickness from spreading. Plants treated with pesticides and herbicides should also be kept out of the bin, since these plants could poison your compost bin with their sprays.
Think about it: a compost bin depends on worms and insects to aid in decomposition. Meanwhile, plants coated in pesticides are going to kill the life within the heap. By poisoning those creatures, the compost is damaged, and the toxins will spread into the water table, and beyond. It’s not a healthy system, and should be avoided at all costs.
Keep sprays far from your garden. In fact, it’s important to find as many natural ways to deal with weeds and pests as possible. Your garden and your compost bin will thank you.
Your compost bin can handle newspaper, and printer paper, sketchbooks, and notebooks. Glossy magazine paper and old political flyers are a different story. That shiny coating they use to catch your attention is a compost killer. Keep coated papers out of the compost bin. They just don’t decompose well.
The coated outer layer of these shiny pages are full of chemicals and microplastics. These pages are a mess in compost bins and bonfires. They’re also a mess in landfills. Dump them in the recycling bin instead.
The Jury is Still Out On These:
There are a few items of debate in composting circles. If you want an easy, low-maintenance bin, you may want to avoid these controversial additions. Of course, these often-debated options have a lot of benefits as well.
I love to dump dairy in my compost heap, as it’s a super food for soil. Milk products and the microbes that feed on composting milk are excellent for the garden. In fact, ancient cultures used to pour milk directly onto their fields in harvest fertility rites.
That said, dairy can cause some problems as well. Wild animals are attracted to milk, and it can attract flies as it decomposes. This is an easy issue to avoid: simply pour your dairy products in under a layer of older compost.
Note that if you keep the milk under cover, it’s an asset to composting.
Sawdust and Wood Ash
Some people are strongly opposed to adding wood by-products to the bin, as they can quickly take over your heap if over used. Of course, in moderation, sawdust and wood ash can also be helpful.
Sawdust’s primary benefit is its ability to balance out nitrogen-heavy compost like chicken manure by adding much-needed carbon. Wood ashes contain no nitrogen, but plenty of healthy trace minerals. Adding wood ash to your compost bin can be a valuable source of lime and potassium.
Both materials reduce odor and help break down organic matter faster. But don’t over do it. A sprinkle or two on top of some old milk or eggs shells is enough. If you don’t let these materials take over, they’ll be a great addition to the heap.
If you don’t spray your lawn, grass clippings can be a reliable source of nitrogen in your compost bin. But, like wood-products, grass clippings can easily overtake your compost. Add lawn clippings with sawdust to balance the nitrogen or your compost will become too hot (nitrogen-heavy) and burn your plants.
I find 1 part sawdust to 10 parts grass clippings to be a great balance. If you aren’t also adding chicken manure to your compost, you could even mix 1 part sawdust with 20 parts grass clippings for a safe ratio. It’s all about moderation. If you don’t want to play the mixing game with your compost heap, leave out the grass clippings.
Everything Else is Easy!
Reading a whole list of don’ts can feel overwhelming sometimes. But then again, I’m pretty sure you weren’t planning on dumping human waste, shampoo, and glass jars in your compost anyway. Right? This list is just a reminder to trust your instincts.
If something seems like trash instead of compost, toss it. Of course, if you’ve got a pile of odds and ends from this morning’s frittata, feel free to bin that stuff. Think about all the carrot ends, onion peels, egg shells, and coffee grounds we waste on a daily basis. Those things make beautiful soil, so help transform them into glorious soil!