Before you try anything: always speak to a professional before cleaning, treating or applying any product to your stone. Every slab is different, and the wrong product can cause permanent damage. Contact us or a qualified stone restorer first.
Quick answer
Turmeric stains in concrete come out with a hydrogen peroxide poultice: wipe up the spill, wash the area, then cover the yellow stain with the poultice for 24 to 48 hours. Curcumin, the yellow pigment in turmeric, fades under UV light, so a few days of direct sunlight on the stain often finishes the job.
First, check what you are dealing with
- Yellow or orange mark: turmeric or curry. Follow the steps below.
- Yellow mark with an oily halo: curry oil too. Do a solvent poultice after the peroxide.
What you need
- pH-neutral dish liquid
- Hydrogen peroxide
- Flour, talc or diatomaceous earth
- Plastic wrap and tape
- Plastic scraper
Step by step
Wash the area
Clean with warm water and a few drops of pH-neutral dish liquid, rinse and dry with a soft cloth so you can see what is left on the concrete.
Test first
Try the mixture on a hidden spot of your concrete (inside a cut-out or under an overhang) and check the finish after it dries.
Mix the poultice
Stir an absorbent powder (plain flour, talc, diatomaceous earth or whiting) into hydrogen peroxide (3% from a pharmacy for fresh stains, or 12% from a hairdressing or pool supplier for older ones) until it has the consistency of peanut butter.
Apply it
Spread it 5 to 6 mm thick over the yellow stain, extending about a centimetre past the edge. If your concrete is sealed, the poultice only works where the stain has got through a worn patch of sealer into the concrete itself.
Cover and wait
Cover with plastic wrap, tape the edges and poke a few small holes so it dries slowly. Leave it 24 to 48 hours until completely dry: the drying is what pulls the stain up into the powder.
Remove and rinse
Lift the dry poultice with a plastic scraper, rinse with clean water and dry the concrete. If the yellow stain is lighter but still there, repeat up to three times.
Let the sun help
Curcumin, the yellow pigment in turmeric, fades under UV light, so a few days of direct sunlight on the stain often finishes the job.
What not to use on concrete
- Vinegar, lemon juice or "natural" citrus cleaners: they etch concrete.
- Scourers, steel wool and abrasive creams on a polished surface.
- Mixing cleaning chemicals, especially bleach with anything else.
- Bleach, which can leave a pale patch in the stone.
When to call a professional
If a yellow shadow persists after poulticing and sunlight, a restorer can treat it. A concrete benchtop specialist can re-hone and refinish the surface and patch chips.
Understanding turmeric and curry stains on concrete
Concrete is porous cement paste. Most concrete benchtops rely on a sealer or wax, so once that coating wears, oil and coloured liquids soak straight in.
A concrete benchtop specialist can re-hone and refinish the surface and patch chips.
Good to know
Turmeric can stain concrete deeply where the sealer is worn. Peroxide and sunlight work, but older stains may need the surface refinished.
Stop it happening again
Whether yours is cast-in-place and precast concrete benchtops, repairing it fixes today's mark; protecting it stops the next one. Our clear Stone Protection Film sits over the surface, so acids cannot etch it and liquids cannot soak in. Choose Gloss for polished concrete or Matte/Satin for honed and matte finishes. The protection is identical. It is installed across Sydney with a 10-year written warranty.
How we protect concrete · Stain removal guide · Turmeric & curry stains on every surface