Don’t put these items in the dishwasher

I think I’d be lost without my dishwasher – it’s quick, easy and more water-efficient than washing by hand.

It helps ease the load of the after-dinner clean-up and saves my lower back hurting from stooping over the sink.

But unfortunately, there are some things that the dishwasher just should not tackle.

Here’s a list of what you can and can’t safely wash in your dishwasher, so you never have to cross your fingers as you open the door after a cycle again.

What shouldn’t go in your dishwasher

Wooden items

Chopping boards, wooden spoons and knives with wooden handles should stay well away from the dishwasher. The heat of the drying cycle is just too much for wooden items. The high temperature can warp or crack the wood and soften or melt the glue that binds them together, causing them to fall apart.

Rinse and handwash wooden kitchen tools soon after you use them, but don’t submerge them in water. If you’ve used the board for raw meat and are worried, try a sanitizing solution of one-part vinegar to four-parts water. A little baking soda can help scrub away stains, too.

Cast iron skillet

Cast iron skillets need special care in the kitchen, they must be seasoned by applying oil several times a year. Putting them in the dishwasher will strip that heard-earned non-stick quality right off. Seasoning prevents the pan from rusting so avoid using dish soap too, just wipe the pan with a paper towel. Stubborn food remnants can be removed with salt and elbow grease. If you need to give it a rinse, make sure to dry it thoroughly after.

Cast iron, when looked after, will last for many lifetimes.

Sharp knives

If you keep expensive knives in a knife block you want to look after them and handwash them. High carbon steel can corrode rapidly in the alkaline environment of your dishwasher and water jets can jostle knives, potentially dulling or breaking the blade.

A blunt blade is not only frustrating, but it’s also more dangerous as it requires more pressure to cut, increasing the chance that the knife will slip with a greater force behind it.

Unloading a dishwasher also becomes a riskier task with sharp blades around. Wash kitchen knives carefully by hand in hot soapy water instead.

Also, knife rivets don’t use the same strength metal as the blade and will wear out more quickly if you put them in the dishwasher, compromising the knife’s integrity.

Fine china or painted plates

These delicate items can chip, fade or lose their finish in the dishwasher. A dishwasher cycle is quite inhospitable, even a gentle one, so keep antique, hand-painted or gold-leaf patterns for the handwashing pile. Fragile items can also be moved and damaged by the strong water jets.

Certain plastics

The quality of food storage containers varies wildly so you should work on a case-by-case basis and go by the manufacturer’s guidance.

Some of the thicker, sturdier cartons will be fine in the dishwasher, place them on the top shelf to avoid warping and don’t try to squeeze them into small spaces. You should know that most clear plastic will get scratched and dulled over time if you wash it this way.

Plastics also tend not to dry very well in the dishwasher as they don’t retain heat that would otherwise contribute to the drying process.

Aluminium cookware

Most aluminium cook and bakeware can technically go in the dishwasher, but they’ll soon oxidise and fade from shiny to dull. Check the label when you buy a new item to be sure, if it’s not specifically labelled as dishwasher safe, best not to risk it.

Crystal

Sometimes it’s best to leave the fancy crystal glassware in the cabinet on display. The dishwasher’s high temperature, alkaline detergents and friction can dull or scratch the surface. Fine crystal also has a habit of shattering when mistreated, and nobody wants to clear that out of the machine.

Any silverware with carved antler or bone handles should stay out of the machine as well.

Wine glasses

Another one for the handwashing pile if you want to keep your glasses scratch-free and crystal clear. Alkaline detergents can slowly dissolve the glass itself, leave minuscule crystal formations after washing, or scratch the wine glass. Handwashing with hard water can cause cloudy calcium deposits on glasses but this can be removed with a water-vinegar solution.

If your wine glasses have lingering red wine stains, use denture cleaner to remove them.

Non-stick pans

The dishwasher will rapidly degrade any non-stick coating on pots and pans; follow the manufacturer’s cleaning instructions to get the best out of them. If they are labelled dishwasher safe, always check for any damage or wear on the coating when you’re unloading.

Thanks to the coating though, they’re generally quite easy to wash by hand.

Delicate metals

Formal dinnerware containing sterling silver, pewter, aluminium, brass, copper or gold can all discolour in the dishwasher. Pewter can even warp due to its low melting point. Keep their gleaming finish by keeping them out of the machine.

Items with printed measurements or directions

Over time, hot water from the dishwasher will fade the markings etched on the sides of measuring cups, rendering them useless. Most glass measuring cups are strong enough to keep their markings for years, but plastic cups may not be as tough. Hand washing them from time to time will increase their longevity.

What goes in the dishwasher

Everyday tableware

Dishwashers are great for pretty much all everyday plates, cups and cutlery. Stack your dishwasher and wait until it’s full to run it to save on your water and electricity.

Pots and pan

Even heavily soiled stainless-steel pots and pans can come up gleaming after a run through the dishwasher. Stuck on food particles that pose a challenge when washing by hand may come right off in the dishwasher when combined with a good quality detergent.

Exhaust fan filters and covers

Place the filters into the dishwasher and run on a hot cycle – a pots and pans cycle is best if your dishwasher has this function.

Kitchen scrubbing brush and sponges

Sponges and scrubbers can be a hive for bacteria when they are caked with food residue. Give them a new lease on life by running them through the dishwasher to disinfect and remove odours.

Lego pieces

Put in a mesh bag on the top shelf to avoid losing small pieces.

Do you have specific tableware for special occasions? Do you wash anything else in your dishwasher? Have you had any dishwasher disasters?

Also read: Seven kitchen organisation tips