Remote diagnosis is never easy. The yellow/green leaves in the first pictures look to be like they may be damaged by mites. Mites thrive in dry, warm weather. San Diego had a very warm July, with average humidity much below average.
This might help:
https://www.fbts.com/battles-i...
and be sure to read Part II as well. This should help you diagnose.
This might not be the problem at all, but mites during the summer can absolutely kill plants. They are ubiquitous in the landscape, and if you do have a problem with them don't be disheartened - as may others will attest the unusually warm weather this summer has made this a real issue.
Kermit
