Oh, it's certainly not going to die, sorry if I made anyone think that. I agree it looks quite healthy overall, but clues like this can point you toward information that may solve sneakier problems.
I guess as someone who lives in an area with alkaline soil, that is what springs first to my mind. Knowing your soil ph can really help choose plants that will do well and understand why others don't.
Also, I don't really fertilize plants in the ground other than mounds of compost, so perusing an unfamiliar isle for a bottle of mystery juice that's going to clutter up the garage for me to use on a single plant and then it might not work anyway (maybe I chose the wrong bottle...). I guess everyone has their own things that are simple.