5 Things You Should Never Put Down Your Garbage Disposal

Your garbage disposal is a helpful kitchen tool, but it’s not a catch‑all for food waste. Many disposal breakdowns and sink clogs start with good intentions and the wrong items going down the drain.

Knowing what your disposal can and can’t handle helps protect your plumbing, avoid messy backups, and extend the life of the unit. This guide breaks it down in plain terms so you can keep your kitchen running smoothly.

What Not to Put in a Garbage Disposal: Protecting Your Kitchen Plumbing

Garbage disposals are designed to grind small, soft food scraps – not to replace the trash can. When the wrong materials are sent through the system, they can dull blades, jam moving parts, or clog pipes further down the line. Understanding what not to put in garbage disposal systems is one of the easiest ways to prevent avoidable plumbing problems.

5 Common Things Not to Put in a Garbage Disposal to Avoid Clogs

Before you flip the switch, keep this short list in mind. These are some of the most common things not to put in garbage disposal units, and why they cause trouble.

1. Fibrous vegetables: Celery, corn husks, asparagus, and onion skins contain long fibers that don’t grind well. Instead, they wrap around the disposal’s components, which can lead to jams and overheating.
2. Fats, oils, and grease (FOGs): Grease may go down as a liquid, but it cools and hardens inside your pipes. Over time, it coats pipe walls and traps other debris, creating stubborn clogs.
3. Egg shells: Despite popular belief, egg shells in garbage disposal units are not a good idea. The membrane inside the shell can wrap around components, while the shell fragments contribute to gritty buildup in pipes.
4. Hard materials: Bones, fruit pits, shells, and other hard items are too tough for most disposals. They can crack internal parts or cause the unit to seize altogether.
5. Starchy or expanding foods: Rice, pasta, oats, and potato peels absorb water and swell. That expansion can turn into a thick paste that slows drainage and causes blockages.

Can You Put Egg Shells in Garbage Disposal Units?

This is one of the most common kitchen myths. While it’s often said that eggshells sharpen disposal blades, modern disposals don’t work that way. They rely on blunt impellers to break food down, not sharp edges.

The thin membrane lining the shell is the real problem, because it tends to wrap around components and contribute to clogs further down the drain. The safest move is to toss shells in the trash or compost instead.

Why Fibrous Scraps and FOGs (Fats, Oils, Grease) are Disposal Killers

Fibrous scraps and FOGs are especially damaging because they don’t just affect the disposal; they impact your entire plumbing system. Fibers can tangle around moving parts and quickly jam the unit, while grease may appear harmless at first, but silently builds up inside pipes as it cools and solidifies. Over time, that buildup narrows the pipe interior and traps other debris.

These issues often start small and out of sight, which is why they’re easy to ignore. Left unchecked, they can lead to slow drains, recurring clogs, unpleasant odors, or even sewer line backups that require professional intervention.

Hard Materials and “Expanding” Foods to Keep Out of the Drain

Hard items stress the disposal’s motor and internal components, increasing the risk of mechanical failure or a complete jam. Materials like bones or fruit pits don’t grind down easily and can cause sudden breakdowns that stop the unit from working altogether.

Expanding foods create a different problem. Items like rice, pasta, or potato peels don’t break down fully and instead absorb water, swell, and thicken inside the pipes.

Ultimately, both put unnecessary strain on your plumbing, reduce proper flow, and raise the odds of an unexpected repair at the worst possible time.

When to Call Howard Air & Plumbing for Professional Disposal Repair

If your garbage disposal is humming, grinding poorly, draining slowly, or not turning on at all, it’s time to bring in a professional. Continuing to use a struggling unit can make the problem worse and lead to water damage under your sink.

The licensed plumbers at Howard Air & Plumbing can diagnose disposal issues quickly, clear blockages safely, and recommend repairs or replacements when needed. When in doubt, it’s always better to call early and avoid a bigger mess later.

For help from a plumbing team you can trust, contact Howard Air & Plumbing today!

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