Why You Can’t Wash Good Knives in the Dishwasher

Dishwashers have made life easy for so many of us. Instead of spending several hours a day in soaking, scrubbing, rinsing and drying our dishes, we now have an easier alternative. But as tempting as it is to throw everything in a dishwasher, there are a few things that still should always be washed by hand. These include fine china, fine crystal and stemware, gold trimmed dishes, wooden bowls and utensils, and high quality knives and steak knives.

While most of us can understand how a dishwasher might damage fine china and stemware, how it could ruin a good set of stainless steel handled steak knives might be a puzzlement to most of us. Here are four reasons why it’s always best to hand wash your new knives instead of tossing them in the dishwasher:

Reason #1: While it’s true that many contemporary knives have handles that are dishwasher safe, it’s the blades that don’t fare well during washing. The jet spray of the dishwasher can cause those knives to bump around and knock against each other, with some even banging against the plates. Over time, all this activity can dull the knife blades.

Reason #2: Dulling the edges of the knife blade is one reason why knives don’t belong in the dishwasher. Damaging the dishwasher is another reason why your good knives should be hand washed instead.

The sharp blades of a knife will cut through plastic utensil baskets and create gaps that other utensils can fall through. And what about the practice of washing larger knives by laying them on the upper racks? The churning movement of the jet spray will set those knives to sawing away at a rack’s plastic coating. Since the racks are made of a metal framework, damaging the plastic coating will make the rack vulnerable to rust.

Replacing damaged dishwasher baskets and racks is not an cheap DIY repair. Most replacement racks start around $80 with baskets running between $45-$75.

Reason #3: Many knives, especially the more decorative kinds can’t hold up to high temperatures and exposure to water. Knife handles made of wood, bakelite or other vintage plastics, horn, and antler quickly deteriorate in a dishwasher and are best washed by hand.

Reason #4: To avoid damaging a dishwasher utensil basket, many of us will assume that placing our knives pointy end up in the basket is a workable alternative. The problem with this is that you run the risk of slicing your hand open by carelessly grabbing a handful of utensils after the dry cycle has finished. Higher risk of injury is just another good reason why knives should never be thrown loose in a utensil basket.

With all the “dos and don’ts” that coming with owning a good set of knives, the best practice is to always hand wash a knife, no matter what the manufacturer’s instructions may read. Not only will you reduce the risk injury to yourself and the dishwasher but you’ll extend the life of your knives for many dozens of years.