How to fix discolored concrete (Eco-friendly)

You may have noticed dark spots or discoloration in your outdoor concrete. This is known as "mottled or pinto concrete". Many things can cause this to happen such as the concrete to water ratio, hard troweled surfaces, improper/inadequate curing, maybe even calcium chloride additives. There is a simple, eco-friendly solution.

Instructions

Difficulty: Easy

Things You’ll Need:

• White vinegar
• Garden hose
• Outdoor Broom

1. Prepare the surface of the discolored areas by hosing off the area, while scrubbing with your outdoor broom.
2. Mottled concrete 'before' Pour the vinegar directly on the discolored area. Do this in the morning and let it sit through the hottest part of the day. Re-apply the vinegar as needed.
   The vinegar and the heat open the pores of the concrete, allowing any trapped moisture to escape and giving you access to the deeper parts of the stain.
3. Mottled concrete Before the day begins to cool, scrub the area with your outdoor broom then hose it off. The stain should be gone, it may even have faded while the vinegar was sitting.

Tips & Warnings

• Do this during the summer
• Best results if concrete is in direct sunlight
• Tougher stains or deeper discolorations may require this to be done more than once.