Can You Compost Onions: How To Compost Onion Peelings
It’s a beautiful thing, how compost turns otherwise useless organic material into prized plant food and soil amendment for the garden. Almost any organic material, unless diseased or radioactive, can be added to the compost pile. There are few restrictions, however, and even those may simply need to be pre-treated correctly before inclusion in your compost.
Take potatoes for instance; many people say not to add them to the pile. The reason in this case is the spuds’ desire to replicate and become more potatoes, turning into a pile of tubers instead of an organic mixture. Squashing the tubers before adding them to the pile will solve this problem. But what about onions in compost? Can you compost onions? The answer is a resounding, “yes.” Composted onion waste is just as valuable an organic ingredient as most any with a few caveats.
How to Compost Onion Peelings
The issue when composting onions is similar to the potato in that the onion wants to grow. To avoid new shoots from sprouting from the onions in compost piles, again, chop it up into halves and quarters before tossing it into the compost bin.
If you are not trying to compost an entire onion, then the question may be, “how to compost onion peelings?” Onion skins and scraps do not result in the growth of more onions, but they may add an unpleasant aroma to the pile and lure pests or wildlife (or the family dog to digging!). Rotting onions really do smell extremely bad.
When composting onions, bury them at least 10 inches (25.5 cm.) deep, or more, and be aware that when you turn your compost pile, the possibility of an unsavory aroma of rotting onion may stop you in your tracks for a moment. In general, the larger the piece of onion added to the compost, the longer it takes to decompose. Of course, this rule applies to all large organic scraps whether vegetable, fruit or branches and sticks.
Additionally, if odor is of primary concern, adding crushed oyster shells, newsprint or cardboard can aid in eliminating or, at the very least, controlling noxious smells.
Last Word on Composting Onions
Finally, composting onions does not affect the microbes present in your compost, perhaps just your olfactory senses. Conversely, onions are NOT recommended for addition to vermicomposting bins. Worms are not big fans of odorous food scraps and will turn their metaphorical noses up at onions as well as broccoli, potatoes, and garlic. The high acidity of composted onion waste does not sit well with worm gastric systems apparently.
Share this on
Send this by
If you have found yourself in the middle of a debate around the dinner table about composting lately, you are (surprisingly) not alone.
As navel oranges come into season and onions find their way into slow-cooked meals, can you just throw their peels into your compost bin?
And what about leftover bread, coffee grounds and cardboard?
"There's nothing to be afraid of when it comes to composting," host of Gardening Australia, Costa Georgiadis, said.
"Composting is the people's art. More money doesn't make better compost."
While that might be music to the average homemaker's ears, composting is indeed an artform, and an area littered with old wives tales.
So if you are in the habit of throwing anything and everything into your bin and leaving it to fend for itself, there are a few things you should know.
Food scraps, newspaper, dried leaves, lawn and plant clippings and untreated wood material are all part of making balanced organic compost. As each of these components decomposes, it adds essential nutrients that attract microorganisms, which further aid the breakdown of materials and scraps. Some people use worms to aid the decomposition process. Worm-aided compost is called vermicompost.
What you add to your compost pile also determines the nutrients that aid decomposition. Materials like untreated wood and dry leaves add essential carbon to your compost, while materials like lawn clippings and fruit and vegetable scraps add nitrogen to the pile. For the most efficient and timely decomposition, it is important that you create a balance between nitrogen and carbon in your compost pile.
Starting compost is as easy as saving your kitchen scraps and throwing them in the compost pile or container. However, for the best results, there are a few rules to composting to keep in mind.
First, it’s essential that you keep the ratio of green material and brown material around 50/50. This means for the same amount of fresh kitchen scraps you add to a compost pile, you should also be adding an equal amount of leaves, cardboard, and sawdust. The bacteria that breaks down the compost needs both of these types of materials to thrive and create rich and healthy compost.
Second, your compost pile needs to be watered just like your garden. This isn’t as much of an issue in climates where regular rain and snow can dampen the compost pile. When your area doesn’t get a lot of rain or snow, or the compost pile is closed off to the elements, a problem arises. A compost pile that is too dry will not break down, and you will be left with a stinky pile of random kitchen bits and leaves.
The third and last thing to remember about compost care is turning it. Like a good chili, you want your compost pile to mix and meld all its flavors together. There are times when worms and other beneficial creatures in your compost bin will favor one area more than another or water may pool in one section while leaving another area dry. Mixing and turning a compost pile prevents this from happening and ensures the compost is decomposing equally throughout.
Less Invasive Trench Composting Method
The one problem that many gardeners have with this style of composting is that it can be invasive to the garden itself. On average, it is not recommended to overwork the dirt, as too much tilling can disrupt garden soil life. Luckily, there are less invasive options that can achieve the same overall result with just a tiny bit more work on your part. (Do Not Disturb!)
One way to do this less invasively is to create a skinnier yet deep trench by moving a shovel back and forth down a line in the garden area.
Then, blend up any kitchen scraps you are hoping to compost by throwing them in the food processor or blender. Ground-up eggshells can also be added to this mix to add extra calcium to your soil!
Then, pour the blended-up food into this smaller trench and cover it up. This is a less invasive process and some of the composting work has already begun by blending the food.
The benefits of composting
Making compost at home doesn’t just lighten our rubbish bin and help our gardens. It also helps tackle climate change.
Each year in Australia, food waste rotting in landfill creates methane equivalent to around 6.8 million tonnes of carbon dioxide. If global food waste were a country, it would be the third-largest emitter of greenhouse gases in the world, behind the United States and China.
So clearly, there are many great reasons to compost. And by following a few simple rules, you too can create your own “black gold”.
Authors: Cheryl Desha, Associate Professor, School of Engineering and Built Environment, and Director, Engagement (Industry), Griffith University
Are Bananas Good for Compost? Bananas (and their peels, once the sticker has been removed) are great for compost. They break down quickly, though, so make sure they’re taken out to the compost pile as soon as possible.
Can You Store Food in Home Depot Buckets? Orange Home Depot buckets aren’t rated as safe for food, although local Home Depot stores might sell food-grade buckets. Read my article on storing food in food-grade 5-gallon buckets (and how to know if they’re food grade) for more information.
Can You Prune Fruit Trees in the Summer or Fall? Fruit trees that need better control and shaping can be pruned in summer. Fruit trees should never be pruned in the fall, as they won’t have sufficient time to recover before going dormant. Read my article on pruning fruit trees in the summer for more details on why fall is a no-go.