Garbage Disposal 101

The garbage disposal is perhaps the single most useful tool in any kitchen. These underrated appliances make cleaning up after cooking and mealtime a breeze, disposing of food scraps with ease. But did you know that you can’t put just anything in your garbage disposal? Here are 10 things you should never put down on garbage disposal.

Coffee Grounds

While coffee grounds seem like the perfect candidate for a trip down the garbage disposal, they aren’t. Used coffee grounds are very densely packed, forming a sort of paste. If you put them in your garbage disposal, they’re likely to end up as a pile of gunk in the drain, clogging the disposal.

Pasta, Grains, and Bread

Pasta, bread, rice, and even oats can seriously damage your garbage disposal and clog your pipes. But why? All of these items expand when wet, which isn’t something you want to happen in your plumbing. While a few pieces of the leftover spaghetti or cooked oatmeal won’t take down your garbage disposal, avoid putting a large amount of any expandable food down your drain — especially uncooked grains and pasta.


As easy as it is to dispose of chicken and fish bones down your waste disposal, they aren’t indestructible appliances. Animal bones are one of the hardest naturally occurring substances around, and your garbage disposal isn’t made to grind down such hard items. While a small fishbone accidentally dropped down the drain won’t be a problem, intentionally putting bones at your disposal will significantly shorten the life of the system.


If you ever find yourself about to drop a handful of nuts down the drain, stop and think about how peanut butter is made. Your garbage disposal is very similar to a nut grinder, and putting any kind of nut into it will result in a sticky paste that will clog up the disposal. It could even cause problems in your pipes.

Shells and Eggshells

Despite the myth that eggshells will help to sharpen your garbage disposal “blades”, you should never put any kind of shell down your garbage disposal. Garbage disposals don’t even have blades — they have impellers that are blunt rather than sharp. Shellfish shells and eggshell membranes can damage your disposal by getting stuck and preventing other scraps from going through the disposal.

Onion Layers and Potato Peels

While diced or sliced onions and small pieces of cooked potato are fine to put down your disposal, their skins can present a problem. The flat, thin nature of both of these items provides the perfect opportunity to slip through the disposal untouched and cause a drain clog. If potato peels do get ground, it will create a starchy paste that can cause problems down the line.

Fibrous Fruits and Veggies

Some fruits and vegetables have fibrous strands that can wrap around the grinder in your garbage disposal and cause it to stop working. Here are a few items you should throw in the trash instead:

  • Celery
  • Pumpkin
  • Asparagus
  • Rhubarb
  • Banana peels
  • Corn husks
  • Pits and Seeds

Similar to bones, fruit pits, and seeds don’t belong in a garbage disposal, especially because smaller seeds can make it through the disposal without being ground. Here’s a good rule of thumb: if you wouldn’t be able to cut it with a knife, your garbage disposal can’t handle it. That means bones and pits belong in the trash.

Grease, Oil, and Fat

While the bacon grease in your pan may be a liquid now, it will congeal over time. Grease, oil, and fat should never be put down your drain, whether you have a garbage disposal or not. To avoid blockages in your plumbing, let grease cool and throw it in the trash.

Non-Food Items

Garbage disposal systems are made to grind up food waste, not to act as a catch-all for trash in your kitchen. Never put anything that isn’t food down your drain, or you’ll find yourself in immediate need of plumbing repair!

If you need garbage disposal repair, call on Norman Air. Contact us today to begin your service request.

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