Cast Iron Tips 5 Mistakes Everyone Makes with Cast Iron (And How to Fix Them)

 Cast iron is almost indestructible — but a handful of common mistakes can ruin your seasoning, cause rust, and turn a beautiful pan into a sticky, frustrating mess. Let us fix all of them today.

By K.B. Shivuri · The Seasoned HearthReading time: 8 minutesApplies to: all cast iron cookware

Cast iron cookware is the most durable, most versatile, and most long-lasting cookware you can own. With proper care, a cast iron pan lasts generations. There are cast iron pots and pans still in regular use today that are over a hundred years old — passed down through families, their seasoning built up over decades of faithful cooking.

But cast iron does have a learning curve. It behaves differently from stainless steel or non-stick, and there are a handful of mistakes that nearly every new cast iron owner makes. The good news: every single mistake on this list is completely fixable. And once you understand what not to do — and why — cast iron becomes genuinely easy to care for.

Here are the five most common cast iron mistakes I see in South African home kitchens, and exactly how to fix each one.

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1

Not Preheating the Pan Properly

Cast iron heats slowly and unevenly at first — it always has a hotter centre and cooler edges. Adding food to a cold or barely warm pan is the single most common reason food sticks to cast iron.

Why it happens: People treat cast iron like a non-stick pan — add food quickly and start cooking. But cast iron needs time. It holds heat incredibly well once hot, but it takes 3–5 minutes on medium heat to reach an even cooking temperature throughout the pan.

The fix: Always preheat your cast iron over medium-low to medium heat for 3–5 minutes before adding any food or fat. To test if it is ready, flick a few drops of water onto the surface — they should immediately sizzle and evaporate completely. If they just sit there and steam, the pan needs more time. If they skitter and jump violently, the heat is too high.

The Seasoned Hearth tip — preheat on the stove, not over a flameFor the most even heat distribution, preheat your cast iron in the oven at 180°C for 10 minutes rather than on the stovetop. This heats the entire pan evenly — including the sides and handle. Remove with oven gloves, add your oil, and cook. This method is particularly good for dishes like bobotie or frittatas that need even heat throughout.

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2

Soaking the Pan in Water

Cast iron and prolonged water contact are enemies. Even a well-seasoned pan will develop rust if left in water — sometimes within an hour.

Why it happens: People wash their cast iron the same way they wash everything else — fill the sink, leave it to soak, come back later. With cast iron, this is devastating to the seasoning and leads quickly to rust.

The fix: Never soak your cast iron. Wash it quickly under warm running water, scrub with a stiff brush or coarse salt if needed, and dry immediately. The best method: rinse, dry with a towel, then place on the stove over medium heat for 1–2 minutes until all visible moisture has evaporated. You will actually see the steam rise as the water burns off. Once dry, apply a very thin wipe of oil while still warm.

Cast iron will rust faster than you expectIn South Africa's humid summers — especially in Gauteng and KwaZulu-Natal — cast iron left wet can develop surface rust within 30–60 minutes. Always dry on the stove after washing. This takes 2 minutes and prevents hours of scrubbing rust off later.

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3

Storing It Wet or Without Protection

A pan that seems dry to the touch can still carry enough microscopic moisture to rust in storage — especially if humidity is high.

Why it happens: After drying what appears to be a dry pan, people put it away in a cupboard. The residual moisture — invisible to the eye — combines with the metal overnight and produces rust.

The fix: Always dry cast iron on the stove over heat — not just with a towel — before storing. After the stove drying, apply the thinnest possible layer of oil to the cooking surface before putting it away. If stacking multiple cast iron pieces, place a folded paper towel between them. This absorbs any residual moisture and prevents the seasoning on one piece from sticking to another.

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4

Cooking Acidic Foods in a New or Poorly Seasoned Pan

Tomatoes, wine, citrus, and vinegar are acidic — and acid strips seasoning. In a new or poorly seasoned pan, a single batch of tomato bredie can take months of seasoning work off the surface.

Why it happens: People use their new cast iron pan for everything immediately — including long-simmered tomato stews, wine-braised meats, and citrus-based sauces. The acid reacts with both the metal and the developing seasoning layer.

The fix: Wait until your pan has at least 4–6 solid rounds of seasoning before cooking acidic dishes regularly. A well-seasoned pan handles occasional acidic cooking without significant damage. After cooking anything acidic, wash and re-season with an extra thin oil layer to restore what was stripped. And cook your tomato bredie in an enamelled pot until your cast iron seasoning is established — then gradually introduce it.

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5

Heating Cast Iron Too Quickly From Cold

Exposing cast iron to sudden, extreme temperature changes can cause thermal shock — and in rare cases, crack the pan. This applies to both heating and cooling.

Why it happens: People place a cold cast iron pan directly over a high gas flame, or run cold water over a screaming-hot pan fresh from the oven. The rapid expansion or contraction of the metal under extreme temperature change stresses the iron.

The fix: Always heat cast iron gradually — start on medium-low and increase the heat over 3–5 minutes. Never pour cold water over a very hot pan. If a pan needs cleaning after high-heat cooking, allow it to cool for 5–10 minutes before washing under warm (not cold) water. The risk of cracking is low with quality cast iron, but there is no reason to take the chance when gradual heating and cooling costs you nothing.

The Seasoned Hearth tip — use your cast iron every single dayThe single most effective thing you can do for your cast iron pan is use it constantly. Daily use means daily cooking with fat, which means daily seasoning layer deposits. A pan used every day is virtually maintenance-free within months. The pans that develop problems are the ones left unused in cupboards for long stretches — moisture, temperature changes, and neglect take their toll. Make your cast iron your default pan for everything and it will reward you.

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Quick Reference — Cast Iron Dos and Don'ts

• DO preheat for 3–5 minutes before cooking
• DO dry on the stove after every wash
• DO apply a thin oil wipe before storage
• DO use it as often as possible
• DO re-season when food starts to stick
• DON'T soak in water
• DON'T put in the dishwasher
• DON'T cook acidic dishes in a new pan
• DON'T heat from cold to high heat immediately
• DON'T store wet or without a thin oil protection

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Frequently Asked Questions

My food always sticks no matter what I do — help!

Sticking almost always comes down to three things: insufficient preheating, not enough fat, or moving the food too soon. Let the pan preheat properly, add enough butter or oil to coat the surface, and then — crucially — leave the food alone. Meat sticks to cast iron when it is not ready to be flipped. When it is properly seared, it releases naturally. Wait for it to release instead of forcing it.

Can I use metal utensils in my cast iron pan?

Yes — unlike non-stick pans, cast iron is not damaged by metal utensils. Metal spatulas, spoons, and tongs are all fine. In fact, a metal spatula is ideal for cast iron cooking — it can get under food and scrape up the fond (the browned bits) without damaging the surface.

How do I know if my seasoning needs to be redone?

If food starts sticking that did not stick before, if the surface looks dull, grey, or patchy rather than dark and shiny, or if you can see rust spots developing — it is time to re-season. This is not a failure, it is maintenance. Clean the pan, remove any rust, and do 2–3 fresh rounds of oven seasoning. Your pan will come back better than ever.

Your Pan Will Forgive Every Mistake

Cast iron is extraordinarily forgiving. It has survived open fires, neglect, rust, and generations of kitchens. Fix your mistakes, re-season when needed, keep cooking. Every South African kitchen deserves a good cast iron pan — and every cast iron pan deserves to be used.

— K.B. Shivuri, The Seasoned Hearth