Remove rust stains from concrete by applying vinegar to the stain, keeping the stain wet, scrubbing with a stiff brush and rinsing the concrete. Vinegar does not stain clothing like commercial rust removers. Avoid bleaching rust stains, as the chemicals react to make the rust difficult to remove.
- Apply vinegar to the stain
Use either cider vinegar or distilled white vinegar to dissolve the rust stain. Pour a generous amount on the stain, and allow it to work a few minutes. The acid in the vinegar helps to dissolve the iron oxide and lift it from the concrete. Avoid spilling any undiluted vinegar on valuable plants or the lawn.
- Keep the stain wet
If the vinegar begins to dry, apply more to keep the area wet with the dilute acid. Continue adding vinegar to the stain so that it sits for a total of 15 minutes.
- Scrub with a brush
Use a wire brush to scrub the stain. Scrub in a circular motion while applying firm pressure. If the stain is old and is not dissolving with vinegar, consider using trisodium phosphate to scrub it away.
- Rinse the concrete
Use a garden hose to rinse away the vinegar and the rust stain.