We just poured a new concrete patio this summer and now it’s all stained from the walnut tree hanging directly over it. Every morning there is black stuff all over it, we hose it off, but there are purple/black stains all over it now. Is there any way to remove these stains? And then prevent them? Other that cutting down the tree, which we are seriously considering.
You can try a Power/Pressure Washer. I’m not sure if it’s stained in the sense that there was a ‘liquid’ that got into the concrete. Yes, concrete is somewhat porous but perhaps it dried quickly enough that it’s not that deep. A water hose only gives about 40lbs of press, give or take.
Have you tried scrubbing lightly (with a Nylon-bristle brush) with household dish detergent (like Dawn or Dove)? Other than that, you can try a ‘true’ concrete cleaner. They sell it at the Home Centers.
My best to ya and hope this helps.
Jay J -Moderator
PS: I’d start by pruning the trees, in the least. After that, if the nuts still pose a problem, you can prune some more or cut them down …