Too much cold or rain recently?

FataMorgana

i saw the same thing on my catmint! and yes, we have had a ridiculously wet spring/winter here in nw georgia.
so this isn't a dire situation, right?

I would expect the plant to recover/get green when the weather gets more normal.

FataMorgana

Do you think above plants have a chance of surviving? They came back this yr and turned brown. I'm in NJ

I have 3 big lemon balm plants and their leaves do this every year. It seems to be an issue of age. The oldest of the leaves/stems turn a reddish purple. And they get tough. I usually use those leaves just as would the green ones because it doesn't affect the flavor. If you don't plan on using the purple leaves, I'd just cut them off. Stem too. You also might want to consider cutting the whole plant back. Lemon balm grows very fast and you'll have an abundance of fresh green growth in no time.