If you have a dishwasher in your home, you’re well aware of its blessings as a time-saver and all-around convenient staple in your kitchen. But there are certain items your dishwasher should never see. Some are pretty obvious, but others may surprise you. While hand-washing is not exactly ideal, in some cases it’s better to handle with care. Here are 10 things you should never put in the dishwasher.

1. Cast Iron Cookware

Cast iron pans and skillets are beloved for their “seasoning,” AKA the layer of oil that’s baked onto your cast iron, which gives a unique flavor to your dishes. However, this seasoning can be easily stripped away by the harsh detergents and high heat of a dishwasher. To preserve the perfect sear and flavors that only cast iron can offer, it’s best to hand wash these kitchen workhorses with care, using minimal soap and hot water and drying it completely right away.

2. Nonstick Cookware

Nonstick cookware is a kitchen favorite for easy cooking and cleanup, but it’s also susceptible to damage in the dishwasher. The dishwasher’s aggressive cleaning methods can lead to the degradation of the nonstick coating, making your once-nonstick pans less effective.

3. Fine China and Delicate Glassware

Your collection of fine china and delicate glassware deserves special attention. The dishwasher’s powerful jets can chip, crack, or break these delicate items, robbing you of your cherished heirlooms. For those special occasions when you bring out the fine china or crystal glassware, always hand wash them with an extra gentle touch to make sure they stay in pristine condition for generations to come.

4. Wooden Utensils and Cutting Boards

Wood and water don’t make a happy pair. The dishwasher’s hot water and prolonged exposure can cause wooden utensils and cutting boards to warp, crack, or split. To safeguard the longevity and hygiene of these kitchen essentials, hand wash them with a mild detergent and avoid soaking them for extended periods.

5. Insulated Travel Mugs and Thermoses

While your dishwasher may seem like the perfect solution for cleaning your travel mugs and thermoses, the tight spaces and high temperatures inside can compromise their insulation properties. A gentle scrub with a bottle brush will keep these items clean and functional.

6. Plastic Containers with Stains

We’ve all had those stubborn tomato sauce stains on our plastic containers. But unfortunately, the dishwasher may not always be up to the task of removing them completely. To tackle these stains effectively, it’s best to hand wash with a mixture of warm water and baking soda. Or just ditch the plastic altogether and go for glass storage containers.

7. Copper Cookware

Copper cookware is known for its stunning appearance, but it requires special care to maintain its shine. The dishwasher can cause tarnishing and loss of luster. Instead, clean your copper pots and pans by hand using a mild copper cleaner when necessary.

8. Kitchen Knick-Knacks

Quirky salt and pepper shakers, delicate ceramic figurines, and wooden decor pieces may add charm to your kitchen, but they are not dishwasher-friendly. These items are often fragile and susceptible to breakage in the dishwasher’s turbulent environment. Treat them with the care they deserve by hand washing and handling them gently.

9. Sharp Knives

Dishwashers can be particularly rough on your knives, dulling their finely honed edges and potentially damaging the handles. Additionally, the blades may knock against other items in the dishwasher, risking chipping or breakage. To maintain sharp blades and safe handling, always hand wash your knives with care, keeping them away from other items that may cause damage.

10. Kitchen Gadgets with Electronics

This may seem like the most obvious, but it’s still worth noting. Modern kitchen gadgets often come equipped with electronic components that should never be exposed to water. Even things like electric can openers or coffee makers with electrical parts can suffer irreversible damage if placed in the dishwasher. Cleaning these may vary, so, always follow the manufacturer’s cleaning instructions and hand wash any detachable parts.