Short answer, no, sorry.

Nope, not in my experience.

Hi, welcome to GoY, I think it would be more likely to act as a fertilizer than a weed killer, when I was at school, {many years ago} the rural science teacher used to put tea leaves on his pelargomium plants to make the leaves greener, but to be honest I never really noticed any difference between his plants and mine, and I didn't use tea leaves, but it would certainly not act as a weedkiller, Derek.