Never Put These 18 Things in Your Compost Bin - Backyard Boss
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Never Put These 18 Things in Your Compost Bin

One of the most rewarding ways to reduce household waste while helping your garden prosper is to compost organic waste. Composting can be beneficial in many ways whether you live in the countryside with plenty of nature or an apartment with a garden on your balcony.

Compost naturally makes for a rich fertilizer. The richer the soil, the healthier the crops. However, that doesn’t mean soil will accept anything and everything. Soil isn’t picky, but to make your own fertilizer for free, you’ll need to keep an eye out for things that should never enter the compost bin.

Ensure that your compost bin is free from these 18 things to prevent pests, parasites, diseases, and even wild animals!

1. Meat and Fish Scraps

While composting is a way to dispose of organic material, there are some rules to the process. It is best to avoid meat and fish in your composting. When meat and fish start decomposing, they can become grounds for diseases such as E Coli. This can be transferred back to humans if the compost is used in a vegetable garden! In addition to health concerns, fish and meat emit unpleasant odors when they break down.

2. Dairy, Fats, and Oils

Another group of organic materials that should not be composted is dairy, fats, and oils. These can attract pests and emit unpleasant odors. They pose their own unique set of challenges as well. One big reason to exclude these items from your compost bin is because of the negative impact they can have on the success of the composting process. Foods with high-fat content can slow down the composting process.

3. Plants or Wood Treated With Pesticide

Pesticides are commonly used to ward off insects from damaging plants and trees. Compost is one environment where a thriving ecosystem of organisms is necessary to break down organic matter and create fertilizer. Hence, it is best to avoid adding wood or plants with pesticides in them to the compost bin. Pesticides can also impact what the compost can be used for. If you are hoping to use it in a vegetable garden, some pesticides can harm humans.

4. Black Walnut Tree Debris

Black walnut trees are unique because their debris contains toxins. The leaves, bark, and hulls all contain toxic chemicals. This makes them less than ideal for compost. If you are a more experienced composter, it is possible to include these plants in your compost if you give them enough time to break down. However, if you are just learning how to make compost, it is best to avoid debris from these trees.

5. Insect-Infected Plants

It is best to avoid putting plants that are infected with insects into your compost. Some garden pests, such as aphids, find the compost to be the perfect place for a feeding frenzy. In addition, this can spread dangerous insects throughout your garden. The only way that it is possible to compost insect-infected plants is if you have access to something called a ‘hot compost’. In hot compost, the heat of the compost kills any harmful insects or bacteria.

6. Weeds

Similar to many of the materials on this list, the concern about putting weeds in your compost bin exists because of the impact they could have on your future garden. Some weeds are fine to compost as you can easily remove their seeds to prevent their future spread in your garden. If you don’t mind certain weeds taking over your garden or yard, they can be healthy for pollinators such as bees. Soil-friendly weeds include dandelions, mugwort, purslane, clover, pennycress, chickweed, and lamb’s quarter. That said, there are some plants that you will want to avoid, including certain varieties of thistle that can wreak havoc in your flower beds.

7. Charcoal Ash

Charcoal ash is another item that should be avoided in the compost. Some kinds of burned wood are beneficial to include in the compost however, charcoal isn’t one of them. This is because charcoal contains potential additives that could be harmful to plants and there is a possibility that they could be dangerous for humans as well.

8. Pet Poop

It is technically possible to compost dog and cat poop. However, it should be avoided at all costs if the compost is going to be used in any kind of crops or garden plants that will be consumed by humans. Much like animal products, dog and cat feces can contain harmful bacteria such as E Coli that can be passed to humans.

9. Tea and Coffee Bags

Although coffee and tea may seem like they would be good items to include in your compost bin, there are a few things to keep in mind. Due to the chemical makeup of coffee and its antibacterial properties, coffee can impact the effectiveness of your compost. The most useful and nutrient-rich compost is a great environment for microbes to aid in breaking down everything in the compost. There are some similar issues with tea, however, tea can be even more complicated if it is in tea bags. Some tea bags have a small amount of plastic in them that can be harmful to the compost.

10. Citrus Peels and Onions

Worms and microorganisms are compost’s best friends. This means it is important to avoid overly acidic items in the compost, as this can harm these helpful critters. Onion and citrus peels are commonly composted. However, if you want the healthiest compost, opt out of throwing scraps from these foods in your compost.

11. Glossy or Coated Paper

Paper is generally a great item for composting. However, you must be cautious of the materials it is made of. Glossier papers such as magazines or specialty papers like wax paper often don’t compost well. This is because many chemicals are used to create these kinds of paper. A lot of these chemicals release dioxins, which are seriously damaging to any living systems and the broader environment.

12. Sticky Food Labels

Unfortunately, most fresh produce bought from the store has a sticky label on the peel or side of fruit. This can be a nuisance to keep away from the compost pile. These stickers are almost always made of plastic. This means that while the rest of your compost is breaking down into a beautiful fertilizer, the stickers will not decompose and they might leach toxins into your soil. Always discard these stickers before adding the foods to your compost bin.

13. Treated Sawdust

As mentioned previously, wood products are often good for compost. However, when these wood products are treated with chemicals, this can damage your garden and the environment. Sawdust is another item that falls into this category. Although some sawdust is natural, much of it is treated and should not go into the compost bin.

14. Bread

Whether bread products should be composted or not is a subject of debate. However, it is important to remember that bread can attract pests to the area, especially if the product includes dairy. We prefer not to add bread because of how quickly it molds, and how easily it attracts pests.

15. Raw or Cooked Rice

It is possible to compost rice if you are an experienced composter, but it is best to skip including this in your compost for the average composter. Rice can attract pests, especially rats! Also, there are unique kinds of bacteria that can grow from cooked rice. Although some bacteria are good for compost, unwanted bacteria can be harmful.

16. Tomatoes

One unique reason why tomatoes and tomato plants may need to be excluded from composting is how sturdy tomato seeds are. Often compost is not enough to break down tomato seeds. This means that future tomato plants could pop up in unplanned spaces in your garden! Although this might not be an unwelcome development for some gardeners, there are a few other things like the diseases tomato plants can get that make them less than ideal for the compost.

17. Manure From an Animal Taking Antibiotics

Manure is widely known as being one of the best materials to make fertilizer from. Problems occur when the animals that produced the manure are/were taking antibiotics. Using manure from these animals can be detrimental to your health. This is because it can contain and spread infections that are resistant to antibiotics.

18. Inorganic Materials Like Polyester, Rubber, Plastic

The biggest reason to exclude inorganic materials from the compost is a simple fact that they do not break down and might release harmful chemicals. This is the reason why people are slowly moving away from the use of plastics, simply because they’re nearly indestructible. Rubber degrades, but it’ll take years for it to decompose. Rubber bands can take up to one year to “begin” to break down, while the rubber soles in your shoes will take anywhere between 50 and 80 years to decompose!

In Summary

When it comes to composting, there is a learning curve when determining what can and cannot be composted. This list is a great start to keep in mind as you begin your compost. Although it may seem complicated at first, the benefits of composting for your garden and for the environment are beyond worth it!