My laundry started smelling musty even right after a wash cycle. Clean clothes, fresh out of the machine, smelling vaguely of a damp basement. I blamed the detergent. I blamed the humidity. I bought scented dryer sheets. None of it helped because the problem was the machine itself.

Washing machines — especially front-loaders — collect gunk. Detergent residue, fabric softener buildup, mildew, and the general grime of dirty laundry water all accumulate in places you cannot see. Your machine is cleaning your clothes with dirty parts. Eventually the whole thing needs a deep clean, and it takes about half an hour.

The Gasket (Do This First)

On a front-loader, peel back the rubber gasket around the door opening. I almost gagged the first time I did this. Black sludge, hair, a stray coin, and a smell I cannot describe politely. Wipe it all out with a cloth and a spray bottle of equal parts white vinegar and water. Get into every fold of the rubber. This is where most of the smell lives.

The Cleaning Cycle

Pour two cups of white vinegar into the detergent dispenser and run the machine on the hottest, longest cycle with nothing in it — no clothes, no detergent. The vinegar dissolves mineral buildup and kills mildew.

When that cycle finishes, sprinkle half a cup of baking soda directly into the drum and run another hot cycle. The baking soda deodorizes and scrubs off any remaining residue.

Do not mix the vinegar and baking soda in the same cycle. They neutralize each other and you end up with salty water that does not clean anything. Two separate cycles. Vinegar first, baking soda second.

The Filter (If You Have One)

Most front-loaders have a small access panel at the bottom front. Behind it is a drain filter that catches lint, coins, and whatever falls out of pockets. Unscrew it slowly — water will come out, so have a shallow pan and a towel ready. Clean the filter under running water and screw it back in.

I found a bobby pin, two dimes, and something I think was once a gummy bear in mine.

Ongoing Prevention

• Leave the door open between loads. A closed door traps moisture and mildew thrives in it. Even just cracked an inch makes a difference.
• Use less detergent. More detergent does not mean cleaner clothes — it means more residue for mildew to feed on. Two tablespoons of liquid detergent per load is enough for most machines.
• Wipe the gasket dry after the last load of the day. Ten seconds with a rag.

After the deep clean, my laundry smelled like nothing — which is exactly what clean laundry should smell like. No perfume, no must, just fabric. I do the vinegar and baking soda routine every three months now and the smell has not come back.