How to Season Cast Iron Grill Grates

What seasoning actually is

Seasoning is layers of polymerized oil bonded to the cast iron surface. Heated oil molecules cross-link into a hard, food-release layer that also seals the iron from oxygen, preventing rust.

A well-seasoned grate looks dark gray to black, not bare metal silver.

From new (90 minutes)

1. Wash and dry the grates thoroughly. Even invisible moisture causes problems.
2. Apply a thin layer of high-smoke-point oil to all surfaces with a lint-free cloth. The key word is thin — wipe back until the grate looks dry, not glossy.
3. Bake on the grill at 400–450°F for 30 minutes. Smoke is normal and subsides.
4. Repeat 3–5 times. Each pass deepens the seasoning.
5. Cool the grates with the grill off.

Maintenance seasoning

After every deep clean (typically twice a season), repeat steps 2–3 once. This keeps the seasoning healthy.

What to avoid

• Too much oil. Gummy spots come from over-oiling. Wipe back hard.
• Olive oil and butter. These don’t polymerize cleanly.
• Water rinses on bare cast iron. Always dry immediately after washing.
• Storing damp. Damp cast iron rusts overnight. Always dry then oil.

Reviving rusted grates

1. Scrub rust off with steel wool or a wire brush.
2. Wash with hot soapy water (it’s the only time soap is allowed on cast iron) and rinse.
3. Dry completely on the burner.
4. Re-season from scratch.

Cast iron vs porcelain-coated cast iron

Porcelain-coated grates don’t need seasoning but can chip. Once chipped, the exposed cast iron rusts. Repair by sanding the chipped area to bare metal and seasoning that spot.