10 Things You Should Never Put in the Garbage Disposal

garbage disposal


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garbage disposal

Garbage Disposal No-Nos

The garbage disposal feels like the perfect solution to leftovers causing a stink in the kitchen, but hold up. Plumbers list the worst items to put down the disposal because they're the best items to start a clog. Here's what you need to know about using your garbage disposal. 

Under the sink.

How the Disposal Works

You might be surprised to know there's no blender-like blade in the disposal. Garbage disposals have a metal cylinder that spins and forces food particles along a stationary grind plate where it gets broken up. From there, water flushes the particles out through the wastewater pipe. But it can't break everything up.

Leftovers from Plate Thrown into Bin Filled with Food Scraps

1. Food Scraps

The disposal is not designed for the kids' unfinished dinner or the vegetable scraps on your cutting board after making a salad. Instead, scrape plates, bowls, pans, and cutting boards into the garbage or the compost. So, what else shouldn't be going down the garbage disposal? 

Cropped view of female hands peeling apple over Food waste disposer machine

2. Garbage

The first rule of garbage disposals is they shouldn't be used for garbage at all. "The garbage disposal is going to grind anything you put in it, but you should never intentionally put something in the garbage disposal," said Levi Torres, owner of High-5 Plumbing in Denver.

Woman turns on water faucet while washing dishes in kitchen
Courtney Hale/istockphoto

3. Leftovers

No food should intentionally be left for the disposal to handle, Torres said. "You should never be putting eggshells or peelings or rice or lettuce or ice cubes. None of that stuff should be going in your garbage disposal." Once plates are scraped, you can rinse what's left.

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Cropped view of female hands peeling potato over Food waste disposer machine in sink in modern kitchen
Instant Noodles in kitchen sink

5. Pasta, Rice, and Grains

Do whatever you want in your diet, but keep glutenous pasta, soft potatoes, sticky rice, and gummy oatmeal out of your garbage disposal. Grain products will absorb water and expand, making an effective material for clogging pipes. "They turn into a glob of dough, those are the nastiest drain blockages you can imagine," said Matt O'Rourke, president of Z Plumberz.

Related: These Pasta Recipes Are Taking TikTok by Storm

Broken eggshell from a few eggs in the kitchen sink, a plate with a fork and spoon
Andrey Atanov/istockphoto

6. Egg Shells

There's another myth circulating that says egg shells sharpen disposal blades. But egg shells are better used as compost material. "They're heavier than the water, so they just sink to the bottom," O'Rourke said. That means egg shells could just sit in the disposal or the pipes.

Related: 32 Ways You're Ruining Your Home and Don't Even Know It

Dirty Coffee Grounds Sink

7. Coffee Grounds

Some home gurus suggest putting coffee grounds down the disposal to eliminate odors, but don't. The garbage disposal doesn't need any caffeine. Like egg shells, coffee grounds are heavier than water and will settle at the bottom, causing clogs in the process. They can go in the garbage or compost.

Cut celery sticks and leaves on wooden table

8. Stringy Vegetables or Fruits

Stringy fruits and vegetables, such as celery, corn husks, and banana peels, can wrap around the blades of the garbage disposal and prevent them from effectively grinding other materials. This can lead to clogs and blockages in the plumbing, which can eventually cause backups and potential damage. Regularly disposing of such materials can also strain and shorten the lifespan of the disposal unit itself.

Paint roller in the tray with white paint.
Maxim Trukhin/istockphoto

9. Paint

You've just painted, and the house looks great. But what to do with the leftover paint? Definitely don't pour it into the disposal or any drain. Paint, grout, and anything latex should be properly recycled. Anything that forms a skin will cure in the drain. If it turns into a solid at room temperature or when exposed to air, it shouldn't go down the drain.

Dirty dishware

10. Grease and Oil

When they're hot, fats, oils, and grease run through the drain, but once they start to cool, they harden along the walls of the pipes, reducing the water flow. Best bet is to keep them out of the drain. You might be able to reuse cooking oil.

Dirty oily pan with cold solid grease saturated fat from bacon after frying macro closeup as unhealthy leftover cleaning job

Where Should Grease Go?

Cooking grease causes headaches for homeowners, plumbers, and the city. When it hardens, it starts a clog, and eventually the water backs up. Let the grease cool then scrape it out of the pan and into your compost or drain it into an old can and toss it when it's full. Using an enzyme-cleaning product can help break up any grease in the pipes.

dirty dishes

So, What Can Go in the Disposal?

First, anything that goes down the sink drain should be biodegradable. Then ask yourself if a cheese grater could break the item up. "The things that can go down are the ones that will break down and aren't heavier than the water," O'Rourke said. When items are heavier than water, they don't flow easily through the plumbing. Instead, they sink to the bottom of pipes and can start a back-up. It's okay to rinse crumbs and soft foods like sauces and fruits off plates and into the disposal.

Ice cubes

1. Ice

There's a myth that putting ice in the garbage disposal sharpens the blades. Not true. It won't sharpen the blades, but a couple ice cubes in the disposal can help knock out any debris in the grinding mechanism.

Orange and lemon zest

2. To Citrus or Not to Citrus?

There are two schools of thought on this. Orange and lemon peels in the disposal can give it a fresh smell and grind up easily. But they also add unnecessary wear and tear to your disposal. The choice is yours.

Picked chicken wing bones in metal bowl, remnants after eating
Robert Ruidl/istockphoto

3. Bones … Maybe?

Your garbage disposal will break up bones, but ideally, they'd go in the compost. Garbage disposals have to work hard to grind them up into pieces small enough to flow through the water system. Give the machine a break and use the compost or trash instead, but don't fret if a small piece goes down the drain.

Wet stainless steel sink with garbage disposal and wire rack with scrub brush laying on it
Susan Vineyard/istockphoto

Tip 1: Clean It Instead

If your disposal starts to stink, which it inevitably will, clean it. Remove the rubber splash guard that fits down in the disposal and clean it off or run it through the dishwasher, Rose suggested. "It gets nasty underneath and causes smells."

Kitchen Sink
Bill Oxford/istockphoto

Tip 2: Run Some Water

The easiest way to maintain the disposal is to run water through it. Run some water after running the dishwasher because that runs through the disposal as well. When cleaning the sink, turn on the water and flip on the disposal for a few seconds.

Fixating on Petty Arguments

Tip 3: Space Out Use

Backups often happen after big cooking days like Thanksgiving or Super Bowl parties when more food goes down the disposal and the dishwasher runs more frequently, O'Rourke said. Try to space out use to give all the gunk a chance to clear. For example, save the second load of dishes for the next morning.

Bio Clean

Tip 4: Green Cleaning

You can also find environmentally friendly cleaning tablets at discount and hardware stores. Just look for one that uses enzymes rather than harsh ingredients that can cause skin irritation and damage to the environment. Enzymes help break up grease and other biodegradable materials. Torres said he uses Bio-Clean in his own drains as monthly maintenance.

Installing Garbage Disposal
Bill Oxford/istockphoto

How to Choose a Disposal

When buying a new disposal, look for one made of stainless steel that reverses direction. Rose said the step up from the base model disposal is worth it because it breaks up gunk much better. "I would never put one of those things in my house after knowing what I know," he said. "It's so much quieter, too."

Plumber fixing a garbage disposal

Find Your Wrench

The disposal has GFCI protection, like bathroom outlets. It will trip if it gets jammed and starts to overheat. So, check underneath the disposal unit for a red button. If it's tripped, leave it off while you use the wrench that came with the disposal to manually turn the assembly from the bottom. Keep the power off while you remove whatever was jammed in there. If you're at all uneasy about doing the work, call a plumber to handle it for you.