I know all too well that knowing what materials to add to compost tumblers can be confusing. It can be difficult to understand what is and isn’t healthy for a composting tumbler, especially when you’re starting out. Since composting tumblers operate differently from regular composting piles, this can add even more confusion to the situation.
Things You Should Not Add To Your Compost Tumbler
I’ve carefully crafted a list of key items below so you know what not to put in a compost tumbler to help ensure healthy biodiversity when enriching the soil in a garden.
Worms
In general, composting usually includes worms. They are very beneficial to making compost even more nutrient-rich. However, compost tumblers are harmful to worms and they will die because they will have no escape from potentially extreme temperatures.
Fat or Oil
This includes canola oil, olive oil, butter, margarine, or any lard from plants or animals. These products are too dense to break down in compost and will eventually become rancid. Fats can also include oil-dense foods, like potato chips, pork rinds, or any other food that was fried when making it.
Bones
Many think bones are a great additive to compost since they are all-natural. But unfortunately, it takes a very long time for bones to break down in compost. Therefore, bones are not ideal for creating a good environment in compost.
Pesticide Treated Plants
Do not add any pesticide-treated plants to compost. Transferring pesticides from plants to compost will harm the microorganisms you’re trying to cultivate in the compost.
Diseased or Insect-Infected Plants
Adding diseased or insect-infested plants runs the risk of having the same problems next year. This is because these diseases and insects would not be killed and will grow inside the compost tumbler and may even become stronger.
Treated Wood
Companies chemically treat commercial wood to help the aging process. Companies also often treat wood so it matures properly and insects do not infest it. However, do not add treated wood to compost; it will harm the biodiversity and quality of the compost.
Waste
Pet and human waste can be full of bad bacteria and parasites that are unhealthy to the biome of compost, gardening, and human health. Therefore, do not add cat, dog or human waste to a compost tumbler.
Dairy
When pondering what not to add to a compost tumbler, it’s important to note that dairy products are a “no, no”. If dairy is added to compost, it will become rancid and smell bad. Dairy is high in fat and has microorganisms that can start a culture of unwanted bacteria that is harmful to the rest of the compost.
Meat
When you add meat to compost, it has the potential to bring with it disease, bacteria, and other harmful pathogens that can infect a garden. Adding meat will also attract unwanted wildlife to forage through the compost because it will start smelling bad, indicating decay and rot.
Black Walnut
You may or may not know that black walnut trees create a chemical called juglone, which is toxic to many different living organisms. Therefore, any microorganisms in the compost and any plants that are grown from it would be harmed by black walnut materials.
Plants That Have Gone to Seed
Putting plants that have gone to seed in a compost tumbler allows seeds to remain dormant. Once you spread the fresh compost out in the garden, the seeds will be exposed to the sun and start growing again. This will cause a big problem when weeds or other unwanted plants start crowding out plants in the garden.
Charcoal Ash
Most charcoal has additives to keep it burning, and it can also contain metals that are harmful to plants. For these reasons, you should not add charcoal ash to compost.
Rice
Rice left out for a long time is harmful because it creates and harbors bad bacteria. When you add rice to compost at a higher temperature, bad bacteria can multiply and create an environment that is harmful to plants and people.
Bread or Baked Goods
When bread or baked goods are placed in compost, they degrade well but give pests a reason to rummage through compost. The sweet or yeasty smell attracts these unwanted guests to your compost, which you definitely don’t want.
Glossy Treated Paper
Many times cardboard and paper are treated with a glossy finish or wax. However, any chemical treatment on paper or cardboard will harm compost microorganisms. If you decide to use paper or cardboard in your compost tumbler be sure it is plain with no glossy or waxy finish.
Our Final Thoughts on What Not To Put In a Compost Tumbler
I know composting can seem confusing, especially when first starting. But hopefully, with this definitive list in hand, you should now have full confidence that successful tumbler composting can happen.
Now, you can try out composting with the knowledge that you’re capable of cultivating healthy and thriving compost for your garden!