Washing Locs: The Diluted Shampoo Method for an Itchy Scalp

November 6, 2026

Washing locs starts with a diluted shampoo applied to the scalp, not the locs themselves, and a rinse that runs through the locs without scrubbing them. The locs trap shampoo easily, and the buildup that follows is the most common loc problem. Diluted shampoo, a scalp focus, and a thorough rinse keep the buildup down.

Why locs trap shampoo

Locs are dense, matted hair, and dense hair traps product. Shampoo applied directly to the locs sits in the fibres and does not rinse out cleanly, because the water cannot flow through the loc the way it flows through loose hair. The residue builds up over weeks, and the locs start to feel stiff, look dull, and smell stale, even though the scalp is clean.

The fix is to stop applying shampoo to the locs at all. Apply it to the scalp, where the oil and the dirt actually are, and let the rinse carry it through the locs on the way out. The locs get cleaned by the rinse, not by the shampoo, and the rinse is enough, because the locs themselves are not oily. The scalp is.

The diluted shampoo method

Mix one part shampoo to three parts water in a squeeze bottle, and apply it directly to the scalp in sections. Massage the scalp with your fingertips, not your nails, for two or three minutes, and let the lather sit for a minute. Then rinse thoroughly, letting the water run through the locs, and squeeze each loc gently to help the water through.

The dilution matters because it spreads the shampoo evenly and rinses out cleanly. Undiluted shampoo applied to the scalp in a thick blob will sit in one spot and leave residue, while diluted shampoo reaches the whole scalp and washes away. A clarifying shampoo once a month, diluted the same way, will remove the buildup that does accumulate, and it is worth doing on a schedule, not when the locs already feel stiff.

The itchy scalp problem

An itchy scalp on locs is usually one of two things: buildup, or dryness. Buildup itches because the residue irritates the skin, and the fix is a clarifying wash. Dryness itches because the scalp is not getting enough moisture, and the fix is a light oil on the scalp, not on the locs. The two problems feel the same and need opposite fixes, which is why guessing is expensive.

The test is simple. If the scalp itches and the locs feel stiff or look dull, it is buildup, and a clarifying wash will help. If the scalp itches and the locs feel fine, it is dryness, and a light oil massaged into the scalp will help. Do not scratch with a comb or a sharp object, because a scratched scalp on locs is hard to heal and easy to infect.

Drying, and the mildew problem

Locs that stay damp will develop a mildew smell, and that smell is hard to remove once it sets in. After washing, squeeze the water out of each loc gently, wrap them in a microfibre towel or an old T-shirt for twenty minutes, and then let them air dry fully. Do not tie them up wet, and do not sleep on wet locs, because the dampness sits against the scalp all night.

If you are short on time, a hooded dryer on low heat will dry the locs in under an hour, and it is worth using. A loc that is fully dry will feel light and springy. A loc that is still damp will feel heavy and cool to the touch. Check the thickest locs before you call it done, because they dry last.

Keep reading: Washing Braids Without the Frizz: The Diluted Shampoo Method, Step by Step, Scalp Exfoliation: Before Shampoo, After, or a Different Day Entirely, and Hard Water Buildup on Wash Day: The Chelating Wash, Done in the Right Order cover the nearby cases in this series.

Frequently asked questions

How often should I wash my locs?

Every one to two weeks is the usual cadence, and weekly is fine if your scalp gets oily or you work out often. Locs do not need to be washed as often as loose hair, but a scalp that is not washed will itch, flake, and eventually develop buildup that is hard to remove.

Should I dilute my shampoo for locs?

Yes. Diluted shampoo spreads evenly across the scalp and rinses out cleanly, while undiluted shampoo sits in the locs and leaves residue. Mix one part shampoo to three parts water in a bottle, apply it to the scalp, and let the rinse carry it through the locs.

Can I use conditioner on locs?

Lightly, and only on the length, not the scalp. A heavy conditioner will build up inside the locs and is almost impossible to rinse out. A light leave-in on the ends is enough, and a monthly clarifying wash will remove what does build up.

How do I dry locs properly?

Squeeze the water out gently, wrap them in a microfibre towel or an old T-shirt, and let them air dry fully. Locs that stay damp for a day will develop a mildew smell, and that smell is hard to remove once it sets in. A hooded dryer on low heat helps if you are short on time.