Foods and materials that will jam or damage your disposal
Your garbage disposal can handle soft food scraps, but it will jam, dull, or break on anything hard, fibrous, or starchy. The most common culprits are bones, fruit pits, pasta, rice, and potato peels — all things that seem like they should go down but will either wrap around the blades or expand into a clog. Grease and oil solidify as they cool and coat the blades and pipes, making the disposal work harder and slower until it stops altogether.
The rule is straightforward: if it's harder than a carrot or stringy like celery, it does not belong in the disposal. Anything that expands when wet — oats, bread, pasta — should go in the trash. And anything you would not want to touch with your bare hand should not go down, because eventually someone will have to reach in and pull it out.
Key Takeaways
- Bones, fruit pits, and hard shells will jam the blades or break the motor, so throw them in the trash or compost.
- Fibrous foods like celery, corn husks, and onion skins wrap around the blades and create clogs that are expensive to clear.
- Starchy foods like pasta, rice, and bread expand in water and block the drain pipe below the disposal.
- Grease and cooking oil solidify in the pipes and should always go in a container in the trash, never down any drain.
- Non-food items like rubber, plastic, glass, and metal will damage the motor or create permanent blockages.
Hard foods that will break or jam the blades
Bones — cooked or raw — are the most common reason a disposal stops working. The blades are not designed to pulverize bone; they are designed to shred soft food. A bone will either jam between the blade and the wall of the chamber, or it will dull the blade so much that the motor cannot turn it. Chicken bones are smaller and seem harmless, but they cause the same problem.
Fruit pits (peach, cherry, avocado) and hard seeds are just as damaging. Nutshells, clamshells, and any shell from seafood should go in the trash. If you have a lot of shells or bones, compost them instead — they break down over months and become soil amendment, which is their actual purpose.
Fibrous and stringy foods that wrap around the blades
Celery, asparagus, corn husks, and onion skins are made of long fibers that do not break apart in water. Instead, they wrap around the spinning blade like hair in a drain, creating a tangle that stops the motor and can burn it out. Artichoke leaves, carrot tops, and leafy greens do the same thing. These are all better off in a compost bin or yard waste bin if your city offers one.
Banana peels and citrus peels are thick and fibrous too, even though they seem soft. They do not shred; they wrap. The same goes for the stringy parts inside squash or pumpkin — scoop those out and throw them away before you cut the squash into pieces.
Starchy foods that expand and block the drain
Pasta, rice, oats, and bread absorb water and swell. A small amount might seem fine, but in the warm, wet environment of your drain pipe, they continue to expand and form a paste that blocks the line. This is one of the most common reasons people call a plumber — not because the disposal is broken, but because the drain below it is completely clogged.
Potatoes and potato peels are starchy too. Even if you peel them before cooking, the peels should go in the trash or compost, not down the disposal. when ready mashed potatoes are especially bad — they turn into glue in the pipes.
Grease, oil, and fatty foods
Grease and cooking oil are liquid when hot, so people assume they will wash down. They do — until they cool. Once they solidify, they coat the blades, the chamber walls, and the inside of your drain pipes, making everything sticky and slow. Over time, grease builds up and creates a blockage that is hard to clear without professional help.
Let grease cool in the pan, then wipe it into a container (an old coffee can works) and throw it in the trash. The same goes for bacon fat, meat drippings, and the oil from canned fish. Even a small amount of grease, repeated daily, will eventually clog your drain.
Non-food items that damage the motor or create permanent clogs
Rubber bands, twist ties, plastic bags, and aluminum foil will wrap around the blade or jam it completely. Glass, ceramic, and metal — including silverware accidentally dropped in — will break the blade or damage the motor. Medications, vitamins, and supplements should never go down any drain; they contaminate water treatment systems.
Paper towels, napkins, and coffee filters do not break down in water the way you might think. They stay intact and create blockages. Eggshells are often debated — some people say they are fine, but they do not break down completely and can contribute to clogs over time. It is safer to throw them in the trash or compost.
What to do if you accidentally put something down the disposal
If you hear grinding or jamming sounds when ready after putting something down, turn off the disposal right away. Do not reach in. Fill the sink with water and turn the disposal back on briefly to see if it clears. If it does not, turn it off again and call a plumber — trying to force it can damage the motor.
If the disposal seems fine but the drain is slow or backing up hours or days later, you have a clog further down the line. A plunger on the sink drain might help, but if that does not work, you will need a plumber to snake the line. Prevention is much cheaper than repair.
Frequently Asked Questions
Can I put eggshells down the garbage disposal?
Eggshells do not break down completely and can contribute to clogs, so it is safer to throw them in the trash or compost. Some people do put them down without problems, but the membrane inside the shell can stick to the blades and pipes.
What about coffee grounds?
Small amounts of coffee grounds are generally safe, but they accumulate over time and can create a sludgy clog in the drain pipe. If you use a lot of coffee, compost the grounds instead — they are excellent for soil.
Is it okay to put small bones down the disposal?
No. Even small bones like chicken bones will jam the blades or dull them. Bones are too hard for the disposal to handle and should always go in the trash or compost.
Can I put hot grease down if I run water after it?
No. Hot grease will wash down, but it solidifies as it cools in the pipes below, coating the inside and creating blockages. Let grease cool in the pan, then wipe it into a container and throw it away.
What should I do if my disposal is already clogged?
Turn it off and do not force it. Try plunging the sink drain with water in the sink. If that does not work, call a plumber — they have the tools to clear the line without damaging the disposal or pipes.