Cast iron cooking grates are sturdy and efficient heat conductors. They leave impressive grill marks on steaks and chops. Best of all, they can last a lifetime with the proper care.
If you’ve shied away from using cast iron in the past, we’re here to tell you that they’re actually very easy to care for. In this guide, we’ll clue you in on all our best tips on how to clean cast iron grill grates.
How To Clean Cast Iron Grill Grates
1. Begin to season the grates immediately after you purchase them.
When it comes to cast iron, seasoning means to apply a coating of oil along with high heat. This allows the fat to bake into the pores of the metal, which forms a protective coating that wards off rust and eventually leads to a nonstick finish.
Seasoning is a long and steady process. It may take weeks or even months for your grates to achieve that all-important coating that will give them a nonstick quality. Nevertheless, it’s best to start the process as soon as the new grill is ready for action.
First, rinse the grates thoroughly under hot running water. Dry them thoroughly with a clean towel.
Next, heat the oven to 200 degrees Fahrenheit. Rub the grates all over with a coating of neutral oil, such as canola or flaxseed. Don’t be tempted to use cooking spray—many contain lecithin, which can create a sticky, gummy buildup.
Place the grates in the oven and increase the heat to the highest temperature available. After one hour, turn the oven off and allow the grates to cool for two more hours before removing them. The grates are now ready for their first use.
2. Always clean the grates immediately after each use.
The next most important thing to remember is to clean the grates as soon as possible after grilling. We know, we know—it sounds like a major chore, especially when you’re entertaining large groups. But the sooner you get cracking, the easier the job will be.
First, you’ll want to burn off as much residue as possible. For gas grills, you can achieve this step by turning the burners back on for 5-10 minutes. If you’re using a charcoal grill, simply leave the grates over the coals until the grates are cool enough to handle, but still warm to the touch. With a stiff wire brush, scrub the grates until the bars are free of any food particles.
Next, use a spray bottle to apply a solution of one part apple cider vinegar to four parts water. Carefully wipe the grates down with paper towels. Repeat the process as many times as necessary, until the grates are completely free of residue.
3. If desired, you can give the grates an additional cleaning with hot water and mild soap. Just be sure to rinse them thoroughly to remove all the soap, and use a clean towel to make sure they’re completely dry before replacing them. If the grates are still wet when you put them away, they’ll likely rust before you can use them again.
4. Re-season the grill grates by using paper towels to apply a thin coating of neutral oil to each one. When all the grates have been coated, wrap them in aluminum foil and replace them on the grill. Turn the heat to high, close the lid, and heat the grates for about 10 minutes.
5. When the grates are cool enough to handle, remove the layer of aluminum foil. Replace the grates in their regular positions.
Tip: If you have a charcoal grill, you don’t have to light a second fire just to re-season the grates. Instead, place the wrapped grates in your indoor oven at the highest possible temperature (at least 500 degrees) for 10 minutes.
Your cast iron grill grates are now cleaned and seasoned for their next use.
Tip: If you’re putting the grill away for the season, you might want to store the grates separately—inside the house, if possible. Storing them outside—even in a garage or shed—can leave them prone to excess moisture, which leads to rusting. Water is iron’s worst enemy, and essentially the only thing it’s unable to withstand.
Tips on Rust Removal
Speaking of rust: If your grates do show an orange bloom at some point, don’t panic. Cast iron can withstand plenty of abuse, even from rust. As long as the rust hasn’t been around long enough to eat away at the metal itself, the damage isn’t permanent. Admittedly, it’s not an ideal situation, but you’ll be able to get the grates back in fine working order in no time.
Option #1: Soap and Steel Wool
Clean the grill grates thoroughly in a hot soapy sink, using steel wool or a stiff wire brush. Unfortunately, this will strip the seasoning from the cast iron, but it will take all of the rust off as well, which is your top priority.
Rinse the grates and dry them thoroughly with a clean, rough towel. Take care not to leave any moisture behind, or the rust will return in as little as a day, ruining all your hard work. To ensure that they’re completely dry, try leaving them in a low oven (about 200 degrees Fahrenheit) for 5-10 minutes.
Take a look at this video for a visual aid on how to clean cast iron grill grates that have suffered rust damage.
Option #2: Vinegar
Bear in mind that this option only works if you have a sink area large enough to allow all the grates to lie flat.
Make a solution that’s one part distilled white vinegar and one part warm water. Fill the sink with this solution and let the grates soak there for one hour. Scrub them with a wire pad or brush to remove any residue. Rinse thoroughly to remove all the vinegar solution, then let them dry for 5-10 minutes in a low oven.
Option #3: High Heat
For severe rust buildup, heat the grill to its highest setting. The internal temperature should be at least 600 degrees Fahrenheit. Leave the grates in the hot grill for 1-2 hours. Once they’ve cooled enough to handle, rinse them well with hot soapy water, then rinse again to remove the soap.
Option #4: Self-Cleaning Oven
This is similar to the high heat grill technique, except you’ll be using your indoor oven to pull it off.
If your oven has a self-cleaning feature, simply place the grates inside and run them through the cycle. Again, you’ll have to wait until they’re cool enough to handle before removing them and rinsing them in a hot soapy sink. This method will only work as well as the self-cleaning cycle itself, so we would recommend trying it only if you’re confident that your oven is up to the task.
Option #5: Oven Cleaner
Oven cleaner is a cleaning agent that usually contains lye, an alkaline solution that’s strong enough to unclog drains. Incidentally, it will also remove a heavy buildup of rust from your cast iron grill grates.
In addition to oven cleaner, you’ll need a few heavy-duty garbage bags, protective gloves, safety glasses, and a container large enough to hold the grill grates. Once you’ve thoroughly coated the grates with the cleaner, seal them tightly in the garbage bags and place them in the container. Store the container in a warm, safe place for two days. Be sure that the container is stored in a spot where no children or pets can access it.
After two days, remove the grates and rinse them in hot soapy water to remove the residue.
With the proper maintenance, cast iron grill grates just might last longer than the grill itself. While they definitely require regular care, the process is fairly simple as long as it’s taken care of right away. When you see the results, we’re sure you’ll agree that the effort is worth your time.
Best of luck, and happy grilling!