Seasoning Cast Iron Grates on Slide-In Ranges

What seasoning a cast iron grate means

Cast iron grates sit over the burners on many gas slide-in ranges. They are heavy, they hold heat, and they are meant to last through years of cooking. Over time, constant heat and washing can wear away the dark coating on the iron surface, leaving it dry, gray and more likely to rust.

Seasoning is the protective layer that forms when a very thin film of cooking oil is heated on the iron. The heat changes the oil into a hard, smooth coating that resists moisture and makes food residue easier to wipe off. The same idea is used for cast iron cookware: a lightly oiled surface, heated and then cooled, builds the coating over repeated applications.

For a closer look at how grates are shaped and laid out on different ranges, see grate design.

When to season and when to just clean

A new gas slide-in range usually arrives with grates that are already seasoned. You do not need to season them again before the first use. Clean them, dry them and start cooking. Seasoning becomes relevant later, when the surface starts to look bare or gray, or after a deep cleaning has stripped the original coating.

Seasoning is an occasional step, not a weekly task. Between seasonings, the daily routine is simple: let the grates cool, wipe away food residue with hot water and a brush, dry them thoroughly, and rub on a small amount of oil if the surface looks dry. Frequent seasoning is not needed if the grates are kept clean and dry.

If you are choosing a range and want a model with cast iron grates, the gas slide-in range guide covers what to compare: gas slide-in ranges.

How to season the grates in general terms

The exact steps vary by range, and the maker's manual is the final word. In general terms, the process has four parts.

• Remove the grates and clean them so no food or grease remains. A clean surface lets the oil bond evenly.
• Dry the grates completely. Moisture is the main cause of rust on bare cast iron.
• Apply a very thin layer of cooking oil to every surface, then wipe off the excess with a cloth. You want a barely visible film, not a wet coat.
• Heat the grates in the oven on the bake setting so the oil bonds to the iron. Use the temperature and time the maker's manual recommends for seasoning, and let the grates cool in the oven before removing them.

Day to day care for cast iron grates

After cooking, wait until the grates cool, then remove food residue with hot water and a stiff brush. Cast iron grates are heavy and can take more physical scraping than a glass cooktop, which is one reason many gas ranges use them.

Dry the grates as part of every cleaning. Standing water is what starts rust. If you wash the grates in the sink, dry them with a towel and let them air dry completely before putting them back on the range.

For stuck food, heat the grate briefly, scrape it with a brush, or soak it in hot water. Avoid long soaks in cold water, which can be hard on the iron.

More cooktop care steps are in the article on cooktop cleaning methods.

What to avoid when caring for grates

Do not put hot grates into cold water. The sudden change can damage cast iron. Let the grates cool before any cleaning.

Do not run cast iron grates through a dishwasher. The cycle can strip the seasoning, and the iron is left wet, which invites rust.

Do not use oven cleaners or abrasive chemical cleaners on the grates unless the maker's manual says they are safe. These products can remove the protective coating.

If the seasoning wears thin, reapply it rather than replacing the grates. Replacement parts are a later question for the maker.

Safety and the maker's manual

The maker's manual is the source for care instructions that apply to your specific range, including how to remove and replace the grates. Read it before you season or deep clean the grates, and keep it with the other paperwork for the range.

Seasoning involves heating oil in an oven, so the same cooking fire safety guidance applies. The U.S. Fire Administration teaches that you should stand by your pan, turn the burner off if you leave the kitchen, watch what you are cooking, turn pot handles toward the back of the stove, and keep a pan lid or baking sheet nearby to cover a pan if it catches fire. When you heat oiled grates in the oven, stay in the kitchen and keep an eye on the oven until the grates are done.

These messages come from the U.S. Fire Administration's cooking fire safety pages. For a range that fits your kitchen and your cooking style, start with the slide-in range guide.

What to pick for your situation

Questions

Do new cast iron grates need seasoning before first use?

Usually not. Most gas slide-in ranges ship with grates that are already seasoned. Start by cleaning and drying them. Season later, when the surface looks bare or gray, or after a deep cleaning removes the coating.

How often should cast iron grates be seasoned?

There is no fixed schedule. Season when the iron looks dry, bare or rough. Regular cleaning and thorough drying do more for the grates than frequent seasoning.

Can cast iron grates go in the dishwasher?

In general terms, no. Dishwasher cycles can strip the seasoning and leave the iron wet, which encourages rust. Wash the grates by hand, dry them completely, and reapply a thin oil layer if needed.

Which oil should I use for seasoning?

A common choice in general terms is a cooking oil with a high smoke point, such as vegetable or canola oil. Apply a very thin layer and wipe off the excess before heating.

Should I use the broiler to season grates?

Use the bake setting, not the broiler. The broiler is not designed for heating oiled grates evenly. Follow the maker's manual for the temperature and time.

Is it safe to season grates in the oven?

Yes, when you stay nearby. The U.S. Fire Administration says to stand by your pan and turn the burner off if you leave the kitchen. The same message applies while oiled grates are heating: stay in the kitchen and keep a pan lid or baking sheet nearby.