All it took was a spray bottle with 6% vinegar, a abrasive spo

In the past, we have been hired to clean certain neighborhood street signs like this.

TEXASGIRLMAMMA :
We spray it on using a pump up sprayer. We did this early in the morning as the solution tends to dry quickly if it is too hot. We let it set for just a few minutes. In most cases we give it a second shot of solution.

TEXASGIRLMAMMA :
To kill weeds I would normally use a much stronger solution of vinegar (30%). We rinse the signs with water after the cleaning and also use some additional water to rinse the area under the signs. So far we have not seen an issue with impacting the grass under the signs. I just purchased a couple of gallons of 5% vinegar from COSTCO but any supermarket should have it. With the rinse water, the very dilute vinegar should not be an issue. I wore goggles to protect my eyes but did not have any issue with skin contact from the vinegar.

CBloch : Kudos to you for taking the initiative to improve things in your neighborhood....There are many things that can be done by the citizens and the government doesn't have to do everything.....You probably just saved folks some tax money that would have eventually been spent on a crew to clean that...Again, nice work!.....

CBloch :
Oh wow, what a difference that makes! Thank you for doing that. The ones in my area look pretty good but if I see one that's bad I know what to do.

TEXASGIRLMAMMA :
works good on shower doors, just spray on and wipe off while you shower yourself. It's really not that smelly or abrasive.

CBloch : That sounds so easy! I wish the city would take care of this now and then. The signs you pictured look like they are new after your cleaning. If the city replaced instead of cleaning it would be so wasteful.

CBloch : Right, I checked with hubby and he gets 30% for the weeds. It works really well.
I wouldn't want it in my eyes either. The goggles are a good idea!

billcherie2 : That is a good idea and it's not a chemical. I'll give it a try!

TEXASGIRLMAMMA :
Just mix a spray bottle with vinegar and dawn, spray on glass door and wipe with sponge and rinse off. Doesn't smell bad at all.

TEXASGIRLMAMMA :
Summers in Houston can be so long and boring.
But hey, my house could use power washing😉

TEXASGIRLMAMMA :
Chemistry Public Service Announcement here:
It's a common household substance. But it is indeed a chemical compound. Pure stuff is acetic acid, naturally formed by fermentation. The bottle you use in the kitchen is a very weak solution.
I'd use goggles for the more concentrated solutions.