We get it—you’re cleaning up after dinner, rinsing off plates, and it’s just so tempting to toss everything down the garbage disposal and move on with your evening. After all, it’s called a garbage disposal. It’s built to chew through food scraps, right?
Well… yes and no.
Your garbage disposal is more like a helpful assistant than a superhero. It’s great at handling soft scraps and small bits, but throw the wrong thing in there, and you could be setting yourself up for a plumbing disaster that smells worse than last week’s leftovers.
Let’s talk about the kinds of things you should never send swirling down your sink—and why your plumbing will thank you.
Why Garbage Disposals Aren’t Meant for Everything
Garbage disposals are designed to grind up small food scraps so they can safely move through your plumbing. They do a great job with soft, biodegradable items in small quantities.
But they’re not meant to handle large amounts of food, non-food items, or materials that expand, harden, or tangle. Even things that seem harmless can quietly create buildup over time or cause wear and tear on the disposal’s parts.
Let’s Talk About Grease
(And Why It’s Your Plumbing’s Worst Enemy)
We’ve all done it. You fry up some bacon or sauté some veggies and pour the leftover grease down the sink with a quick rinse of hot water.
What harm could it do? Turns out—a lot.
Grease is a sneaky villain. It’s liquid when hot, but as it cools in your pipes, it solidifies into a waxy, sticky mess. This mess clings to the inside of your plumbing like glue and traps everything else you rinse down after it. Over time, you’re looking at a full-blown clog that no amount of plunging will fix.
It’s not just your home either. When this happens across neighborhoods and cities, it leads to something called a “fatberg”—a massive, sewer-blocking lump made of grease, soap, and waste. Cities right here in BC have spent millions cleaning these up.
What to do instead: Let grease cool, then pour it into a jar or can and toss it in the trash. Even better, collect used grease in a container you can reuse for multiple cleanups.
Coffee Grounds: The Pipe-Clogging Ninja
Coffee grounds may look like fine powder, but when they collect in your pipes, they form a thick sludge. This can cause gradual buildup that reduces water flow and contributes to blockages—especially when mixed with grease or soap residue.
What to try instead: Coffee grounds make great compost or can be used in the garden to enrich soil. They’re also helpful as a natural deodorizer for trash bins or compost containers.
That Old Eggshell Myth? Time to Crack It
You may have heard the old idea that eggshells help sharpen disposal blades. But modern disposals don’t have blades—they use blunt impellers to push food against a grinding ring. And eggshells, particularly the thin membrane inside, can wrap around those impellers and create jams.
The shell fragments can also combine with other materials in your pipes to form sediment-like buildup.
What to do instead: Compost them, or toss them into the garbage after rinsing them out. Some gardeners even crush them and add them to soil to help with calcium.
Starchy Foods: Sticky and Expanding
Starchy items like pasta, rice, potatoes, and bread might seem like easy candidates for the disposal, but they can create a paste-like substance once inside your plumbing. As these foods absorb water, they swell and stick together, slowing down the flow and increasing the chance of a clog.
If you have leftovers to dispose of: Scrape them into the compost bin or trash. And if small amounts make it into the disposal during rinsing, run cold water for a good 20–30 seconds to help flush the pipes.
Fibrous Vegetables: Stringy and Problematic
Certain vegetables—like celery, asparagus, corn husks, and even artichokes—have long, fibrous strands. These strands can wrap around the disposal’s moving parts, tangling the mechanism and reducing its ability to grind.
Over time, they may also create snags within the plumbing, making it easier for other debris to get stuck.
Better to do: Toss these types of veggie scraps in the compost pile or garbage. If you’re unsure, think about how tough they are to chew—that’s often a good indicator.
Bones, Pits, and Hard Objects
It’s easy to think your disposal is tough enough to handle a small chicken bone or fruit pit—but these hard objects can do real damage.
They can crack the grinding components, dull the impellers, or jam the entire mechanism. Even if they make it through the disposal, they may get lodged deeper in the plumbing system, where they’re much harder to remove.
To be safe: Discard bones, pits, and other hard food waste in the trash. If you cook with them often, consider keeping a small container nearby during food prep to collect them easily.
Onion Skins and Thin Peels
At a glance, something like a papery onion skin or a thin carrot peel doesn’t seem like much of a risk. But these lightweight scraps can bypass the grinder entirely and slip through the disposal without being chopped up. In the drain, they tend to act like a net—catching other debris and slowly forming clogs.
A helpful tip: Collect peels and skins in a bowl while prepping your ingredients, then discard them all at once when you’re finished cooking.
Nut Butters and Sticky Foods
Foods with a thick, sticky texture—like peanut butter, almond butter, or thick sauces—can cling to the inside of the disposal and pipes. They’re difficult to rinse out, and over time, they can catch other food scraps and cause blockages.
Even though they wash off a spoon easily, they behave differently once they hit the plumbing system.
Instead: Scrape sticky foods into the trash first. If you’re rinsing a jar, use a spatula to remove as much as possible before washing it down the sink.
Oatmeal, Quinoa, and Similar Grains
These types of grains can expand several times their original size when exposed to water—especially if they’re already cooked. Once inside your disposal and pipes, they may swell and form a thick, gluey paste that slows or even stops drainage.
Best practice: Discard leftovers in the compost or trash. Rinse dishes thoroughly, and use plenty of water to help carry any trace amounts down the drain.
Non-Food Items: Only Food Should Go In
It might seem like common sense, but just to be clear—non-food items don’t belong in the garbage disposal. Things like twist ties, bread clips, cigarette butts, paper towels, or plastic wrappers can seriously harm your disposal’s motor or clog your pipes.
Even utensils like spoons and forks have accidentally ended up in disposals during busy cleanups.
A small habit to build: Double-check the sink before turning the disposal on. It’s a simple way to avoid unnecessary repairs or damage.
So What Can You Put Down the Disposal?
Despite the list of don’ts, there’s still plenty your disposal can handle when used properly:
- Soft, cooked food scraps in small amounts
- Bits of fruit or vegetable (no peels or pits)
- Citrus rinds (in moderation, they can help freshen the smell)
- Leftovers rinsed from plates after scraping
- Cold water (always run water before, during, and after using the disposal)
The key is moderation, water flow, and mindfulness. When in doubt, compost or trash is often the safer route.
What to Do If Things Go Wrong
If your disposal starts to smell, makes a humming noise, or isn’t grinding like it should, there are a few things you can try before calling a professional:
- Turn off the power to the unit at the breaker or unplug it.
- Use tongs or pliers (never your hands) to check for any visible obstructions.
- Try pressing the reset button underneath the disposal.
- If it still won’t work, or if you hear unusual noises, it may be time to call a plumber.
A Little Care Goes a Long Way
Your garbage disposal is a hardworking appliance. With just a few mindful habits, it can serve you well for years without major issues. By learning what not to put down your disposal—and why—it’s easier to avoid costly repairs and keep your kitchen clean and stress-free.
Think of it this way: every time you treat your disposal with care, you’re also taking care of your plumbing, your home, and your future self.
Need help with a clogged or broken garbage disposal?
Whether you’re in Langley, Abbotsford or elsewhere in the Fraser Valley, our local plumbing team is here to help—whether it’s a minor fix or a full replacement. We’ll diagnose the issue, explain your options clearly, and get things back in working order as soon as possible.
Reach out today to schedule a service or ask a question—we’re happy to help!
