Can You Compost Garlic Skin?

Garlic and onions are the basis of many great meals; naturally, using these ingredients often results in many scraps that need to be disposed of. When getting rid of kitchen waste, I try to put as much organic matter into the compost pile as possible. But experience has taught me that excess garlic can cause some problems.

The skins of garlic have much less of a strong smell and fewer oils than garlic cloves. Placing these in the compost along with the rest of the plant matter from making a meal should be alright. But to make sure there was no unintended harm to composting fresh garlic skins, I did some research. 

Can Garlic Skin Be Composted?

Garlic skins can easily be composted and do not really act as odorous foods in the compost. The garlic peel is usually dry and has no oils or a strong smell. Placing paper towels and brown materials in the compost with the garlic skins can help keep pests out. 

Onion skins can also be composted along with garlic peels. Composting onions has the same effect as composting garlic so other organic materials should be added to start the composting process. In a healthy compost pile adding regular amounts of onion and garlic skins will not negatively affect the decomposition process.

Is Garlic Bad for Compost Piles?

Even though everything organic will eventually break down in a compost pile, we try to keep our composting methods optimized to produce the best soil. Garlic produces oils that kill bacteria and microbes around it. Compost soil is full of microorganisms, and they cannot break down garlic if they die when they contact it.

Over time, the soil moisture, acidity, and constantly adapting microbes will break down the garlic enough that worms and other decomposers can process them. Like spicy foods, garlic can slow down the process of decomposition by lessening the bacteria able to attack the newly added food. The nutrients in garlic are very good for plants, so adding them to your compost is worth it. Just limit the amount that makes it into the soil.

If garlic breath is any indicator, these alliums give off a strong smell that attracts pests looking for food. Wild garlic is a food source for many types of foragers, and they will gladly dig up your compost heap looking for some. Keep pests out of your compost by burying garlic and composting onions in the middle of your pile.

How to Compost Garlic?

If you will be adding garlic to your compost bin, it is important to do it the right way. If you want the nutrients of garlic in your garden but not the acidity and putrid smell, then you will need to take the correct precautions. Different types of garlic going into the compost bin needs to be treated differently. 

Type of GarlicCompost Quick Tip
Garlic SkinsYesAdd more brown material 
Garlic HeadYesCut into pieces
Garlic CloveYesAdd gingerly
Garlic TopsYesCut into pieces
Wild GarlicYesCut into pieces
Garlic BreadYesBreak into pieces
Garlic MustardNoCompost over 150° F

Garlic Skins

The peels can be tossed into a compost bin regularly with no effect on the decomposition process. These should be composted well, as if they are placed directly in the garden soil; they will not break down quickly. Garlic skins add nitrogen to the compost and aid structure building in the soil.

Garlic Head

Garlic bulbs sometimes get old or look diseased. If this is the case, care needs to be taken when composting them. If the garlic is moldy and looks like a diseased garlic plant, then you will need to hot compost it, or you could risk spreading pathogens to your garden. Garlic heads that are healthy need to be cut up to prevent sprouting in the moist conditions of the compost pile. 

Garlic Clove

Sometimes the cloves are too small or not worth cutting up, and tossing them into the compost is easier. Garlic is a good source of nitrogen, but when added to the compost with things like coffee grounds, it can create an unpleasant environment. Coffee grounds have high amounts of nitrogen, too, and plenty of brown waste should be added to offset the acidity.

Garlic Tops

Garlic scraps are the top part of the bulb that sometimes comes attached. Garlic greens can be tossed into the compost like any other food scraps. Diseased garlic leaves should be cut off and disposed of in the home waste bin. Garlic stalks can be added with coffee grounds or tea leaves without the negative effects. 

Wild Garlic

This will most likely be added to the compost from yard waste and is an excellent source of nitrogen. Wild garlic that has already produced garlic bulbs may resprout in the compost pile if not heated up enough. Hot compost will stop garlic bulbs from resprouting but can be hard to achieve at home. 

Garlic Bread

Garlic bread will have higher moisture levels than other types of garlic being added to the compost. Make sure to add brown materials if the garlic oil is butter or fat based as it could slow down decomposition. Garlic bread can attract pests, so bury it deep to avoid high levels of infestation and make sure it is broken into small pieces to speed up its breakdown time.

Garlic Mustard

The challenge with garlic mustard seeds is that they are extremely invasive and will sprout all over your compost. Even in hot compost, it can be difficult to prevent all of the garlic mustard seeds from germinating. You will want to try to cover your compost in black plastic bags to kill the garlic mustard seeds and prevent them from making it into your finished compost. 

Can Garlic Be Put In Worm Bins?

Garlic is not a worm’s best friend. A majority of worms are sensitive creatures and react negatively to strong foods with antibacterial properties. Placing too much garlic into worm bins can throw off the natural balance and make some worms sick. Small amounts of garlic can be added to a worm’s natural habitat without serious consequences. 


Dried-out garlic, garlic stalks, and garlic skins can be added to compost bins with the rest of the day’s kitchen waste. In most cases, a large amount of variety in the organic matter will keep the bacteria flourishing in your worm bin and not cause any problems. Garlic bread can also be added in small amounts as long as most of the fat and oil has been removed. 

Other Anti-Bacterial Plants That Slow Down Compost

 Many ingredients we use in the kitchen can have negative effects if added to the compost. As long as it is organic, it will break down, but the key to a healthy compost pile and quality finished compost is maintaining a balance of inputs. Adding too many plant materials that kill bacteria or slow down decomposition at once can lead to undesirable issues in your compost bin. 

Often when we are cooking food to get over being sick, we will use a lot of ingredients with antibacterial elements. Garlic, ginger, onions, citrus, and various tea spices and herbs are used to make us or our loved ones feel better. unfortunately, if all of the scraps and discarded waste from these end up in your compost at once, it can slow things down. Make sure to add a lot of brown material if you are composting while under the weather. 

Onions are very similar to garlic in how they should be treated when added to the compost. Since onions and garlic are often cooked together, it makes sense to follow the same steps to compost them. Try to cut all unused parts into small pieces and make sure whole bulbs aren’t added to the compost. Onions, like garlic, will sprout if not cut up and can lead to unwanted onions in your garden. 

Onions will attract pests and need to be buried deeply. Plenty of brown materials should be added with onions and other kitchen waste will help it break down faster. Moldy onions and diseased onions should not be out in the compost bin unless you will get the pile very hot. Otherwise, dangerous pathogens could make it into your finished compost. 

Citrus fruits have high levels of acidity and will hurt the microorganisms in your soil and worm bins. Try to only add small amounts of citrus peel to your compost and avoid putting citrus fruit in at all. You can try using the fruit to make insect repellent by letting it soak in vinegar or another solvent and spraying it where bugs hang out.