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We’ve covered Surprising Things You Probably Didn’t Know You Could Clean in Your Dishwasher, so we should also go over Things You Should Never Put in Your Dishwasher. Why? Because you don’t want to break an expensive appliance before its time!!
While some of these items may seem like common sense, others may surprise you. For instance, I had no idea I couldn’t just toss my butter knives in the dishwasher (hint: you may be ruining your butter knives!). And I would have thought the dishwasher would do a great job of cleaning garlic presses and burned pans, but apparently there are better – and quicker – ways to clean these items. Heck yeah!
Check out this list of Things You Should Never, Ever Put in the Dishwasher, so you can keep your dishwasher in good working order for years to come!
For more ways to make your kitchen sparkling clean and organized, take a look at the following helpful tips:
Things You Should Never Put in the Dishwasher
Unless you want your home to turn into a giant bubble bath, use dishwashing liquid for handwashing dishes (and certain DIY cleaning recipes).
Want to make your own cleaning recipes? Check out 15 Natural DIY Lemon Cleaning Products (That Work!) you can make at home to save money.
One thing I learned while working in professional kitchens is how to properly care for kitchen knives, and almost 10 years later, the thought of putting a knife in the dishwasher still makes me cringe!
Placing your knives in the dishwasher is a big no-no. The detergent will dull the knife’s blade, which is not only frustrating as you try to slice and dice, it’s also dangerous, since dull knives are more likely to cut you.
Plus, the hot water and heat in the drying cycle can loosen handles, and sharp edges can damage the protective coating on your dishwasher’s racks and baskets, causing rust to form. Your knives are also more likely to rust in the dishwasher, since it’s such a moist environment.
Hand wash your knives. I like to do this immediately after I’m done using them, and I dry and put them away immediately to prevent rust.
STERLING SILVER KNIVES
Sterling silver flatware typically goes through the dishwasher just fine – except for knives. Many sterling silver knives have a hollow handle. The heat from the dishwasher can cause the glue that holds the blade to the handle to melt and separate. Hand wash instead.
Unlike silver, most of which can go in the dishwasher, gold-colored flatware will discolor in the dishwasher.
ANYTHING MADE OF WOOD
Another big no-no is putting anything made of wood in your dishwasher. This includes cutting boards, wooden spoons and other utensils, wooden bowls – you get the idea. Your dishwashers will strip the oil from the wood, causing it to dry out and split.
To keep your wooden kitchen tools in great shape, hand wash in natural detergent, never soak, dry completely before storing, and condition with .
The harsh detergents and excessively high drying temperatures can take a toll on the nonstick coating, even when it’s labeled “dishwasher safe.” If you choose to wash your pans in the dishwasher, skip the drying cycle, and let them air dry.
Replace your pan at the first sign of damage. When nonstick coating is scratched, chipped, or flaking, it can release dangerous toxins into food.
These toxins can cause a myriad health problems, including testicular, kidney, liver, and pancreatic cancers, low birth weight, weakened childhood immunity, endocrine disruption, increased cholesterol, and weight gain in children and dieting adults.
If you can’t live without your nonstick pans, hand wash them with a soft sponge and natural dish soap. For stuck-on messes, soak pans in soapy water before wiping clean, or use a little baking soda as a mild abrasive.
Cast iron skillets and pans have been around for centuries and they can last nearly forever if they are cared for properly. To keep cast iron from rusting and food from sticking, it must be seasoned with oil, which penetrates the iron and leaves a near perfect cooking surface.
When the cast iron is placed in the dishwasher, the harsh detergent and excessive water strips away the oil and leaves the cast iron unusable, and the seasoning process must be completely started over. This applies to cast iron pots and pans that have outer enamel coatings, as well.
Even if your pan is covered with black crud on the outside and you think the dishwasher is an easy way to get it clean, resist the urge. Use some old-fashioned elbow grease instead.
Garlic becomes sticky when pressed into a paste, meaning bits will get stuck in the crevices of your garlic press. Your dishwasher may not be able to reach all these areas, so it’s best to hand wash it to ensure it gets completely clean.
Aluminum pots, pans, and cookie sheets can technically go in the dishwasher, but they’ll oxidize and fade from shiny to dull after just one cycle. Harsh detergents can also cause pitting and corrosion and leave behind hard-to-remove white spots. Even if the pan is labeled “dishwasher safe,” it’s still best to hand wash.
To remove those white spots, make a paste with cream of tartar and water. Spread the paste over the pan, and scrub away. Then be sure to hand wash next time!
COPPER + OTHER PRECIOUS METALS
Those pretty copper pots could dull or discolor in the dishwasher. Keep brass, bronze, pewter, and silver, gold, and bronze heirlooms out, too – they’ll tarnish and will eventually lose their gleaming finish. Hand wash with a natural dish detergent.
COOKWARE WITH BURNED-ON STAINS
PRESSURE COOKER LIDS
While a pressure cooker pot may go through a dishwasher cycle just fine, you should never put the pressure cooker lid in the dishwasher.
The lid contains the valves that control how well the cooker works. The action of a dishwasher can force small particles of food into the valves and vents and cause the cooker to malfunction (explode). The harsh chemicals can also damage the rubber or silicone seals of the lid.
THIN PLASTIC CONTAINERS
Some softer plastics just can’t handle the dishwasher’s heat and can scratch or even melt. Hardier items like food processor bowls, plastic cutting boards, and mixing bowls can often go in the dishwasher, but most clear plastic will get scratched and dulled over time if you wash it this way.
When you place plastics in the dishwasher, use the top rack, and skip the high heat drying cycle. Remove from the dishwasher to air dry.
GRATERS + SIEVES
Any kitchen tool with sharp edges should not be placed in the dishwasher, including graters and sieves, because they can nick the plastic coating on the racks, causing rust to form. Plus, with all the tiny holes, it’s really difficult to get these items completely clean in the dishwasher. Hand wash for best results.
ACRYLIC OR MELAMINE DISHES
Lightweight, non-breakable acrylic or melamine dishware is very popular due to the bright colors and patterns. Unfortunately, the high water and drying temperatures and harsh dishwasher detergents can ruin them. If you want them to last, be sure to hand wash.
ANTIQUES + OTHER DELICATE ITEMS
Antiques and other delicate dishes, including Depression Glass, milk glass, printed or hand painted dishes, China, crystal, etc. can get ruined in the dishwasher. Even printed measurements on glass measuring cups can be removed from the high temperatures and water pressure of the dishwasher. Delicate items also include repaired (e.g. glued) dishes. When in doubt, hand wash.
Plastic and metal insulated cups, tumblers, and containers are great for keeping hot things hot and cold things cold. Most are constructed with two layers of material with an airspace between the two, which provides the insulation.
While some containers are labeled as dishwasher safe, many are not. It is best to hand wash both plastic and metal insulated containers. If you decide to place one in the dishwasher, put it on the top rack, and skip the high heat of the drying cycle that can cause the seal to break and water to enter the airspace.
PRO TIP: Remove coffee stains from inside your travel mug with a paste of baking soda and water. Use a soft brush or cloth to apply the paste, and scrub gently. Rinse well, and dry with a soft cloth.
For more ways to clean with baking soda, check out 60 Ways to Clean Your Entire Home with Baking Soda.
CONTAINERS WITH PAPER LABELS
If you save glass food jars for storage, make sure to remove any labels before washing them in the dishwasher. If you don’t, the dishwasher will remove the labels, which could then clog the drain and food disposal system.
Sure, your keyboard will come out super clean, but it’ll probably be water logged and won’t work anymore, especially with modern keyboards full of advanced circuitry.
To clean your keyboard the right way, first unplug it from your computer, or turn it off if it’s wireless. Turn the keyboard upside down, and shake it over a trash can to remove most dust and crumbs.
Wipe your keyboard with a lightly dampened microfiber cloth to remove stuck-on grime and greasy fingerprints, then clean out hard to remove debris between the keys with a small brush.
To disinfect, spray a paper towel or cloth with hydrogen peroxide or vodka, wipe your keyboard, and allow to air dry.
You can also remove dust and debris from your keyboard with a bottle of Compressed Air Duster, though you should keep in mind that this is not a natural solution. These dusters don’t just contain air. They actually contain flammable gases such as difluoroethane, trifluoroethane, and tetrafluoroethane, which can cause numerous problems for public health and safety, as well as the environment.
Apparently, some online “hacks” are encouraging people to “cook” in their dishwasher. Huh?
Yep! These tips are actually claiming you can cook foods like fish and eggs by wrapping them up and running them through the cleaning cycle in your dishwasher, but, of course, this is a terrible idea.
First of all, manufacturers do not recommend doing this, and it’s likely unsafe. The heat levels in your dishwasher are not as consistent as your stove, so foods like eggs and fish won’t be cooked enough to prevent foodborne illness.
DISHES WITH BIG PIECES OF FOOD ON THEM
I like to think this tip is common sense, but I guess you never know! 😉
Big pieces of food are another no-no for your dishwasher, since food debris can clog your dishwasher drain or end up all over your other dishes (i.e. not clean). You don’t need to rinse dishes before putting them in the dishwasher, but you should definitely scrape them.
I hope these 21 Things You Should Never Put in the Dishwasher will help you know how to use and care for your dishwasher and keep it in good working order for years to come!
What do you think of these Things You Should Never Put in the Dishwasher? Are they all just common sense? Did I miss any? Please share your thoughts in the comments below!