I have several rosemary bushes in the backyard; I live in San Francisco and rosemary thrives here.
However, the landlord overwatered one of the bushes for several months. It's now got some kind of fungus or root-rot which causes it to look unhealthy and the leaves on some branches to turn yellow. Since then, I've removed the soaker hose he put there, and have been letting it dry out. It doesn't seem to be getting better though.
My question is: is there a way I can rescue this rosemary bush? Should I expect it to recover with mostly dry soil and infrequent watering? Or is it doomed at this point and I should rip it out and plant another one?