If you are regularly fertilizing and watering your lawn, you have surely noticed the strange, unsightly yellow stain that appears on the concrete pathway near the lawn right after the concrete comes in contact with the fertilizer. And you have surely tried scrubbing away those orange patches – to no avail. Don’t worry, those patches don’t have to stay on your concrete forever – here is what causes them and how to remove them.
The orange patches caused on your pathway by the fertilizer is practically rust. Most lawn fertilizers contain iron – when that iron is met by water in places other than the lawn, it quickly becomes rust. The mineral residue then becomes absorbed by the concrete, which is why the stain cannot be scrubbed away.
The best way to remove those rust stains is by using any method used for rust removal. One of the easiest techniques is to apply vinegar that has been diluted 50-50. The stain will probably not go away with one application – you will have to apply it several times, then you will need to scrub the area lightly, rinse it, then repeat. If the vinegar solution does not work, you will have to try other rust removal substances – just be careful, most of them are strong acids that might emanate toxic fumes, so never touch them without wearing protective gear and make sure that the acid is completely removed from the surface of the pathway when you are done. For results that do not stain the sidewalk, look for the best lawn fertilizer that is organic and penetrates the ground versus being washed away.