BTW, I am in California.

Well you have certainly over watered it, stressed it and possibly scorched it when it was stressed. Short of doing a deep root moisture test you have to guess when its ok to return to regular watering. Once you feel it is safe to give it water again I would recommend fertilizing it with a moderate to high Nitrogen fertilizer, something that is 2-1-1 ratio, and has some trace nutrients too.

Giving it a bit of shade might also not be a bad idea since it is clearly in a healing stage. Which also means you should keep a close eye on disease and insects since its more susceptible to it in this state.

Good luck, keep us posted.

Thanks you all very much for your response. I will try to add some nutrient. But I am just wondering that if nutrient was the cause, how come the other two trees grow OK and did not turn yellow at all?

Also, for a 15 feet tall orange tree as this tree is, how robust it is? Would it easily die because of some damage? I though their root is deep enough to heal itself after the problem is fixed. I might be wrong though...

Thanks.

We planted a Valencia last spring and got a LOT of rain and have had yellow leaves for about 6-8 weeks (rain stopped two weeks ago). My hub says fertilize or even transplant, I say it's new and overwatered and probably a little shocky-let her rest.

Any suggestions? How did you go, spinspin? Thank you.

Looking at your picture, it looks like the yellow tree gets more sun earlier. Overwhelmed by sun? Maybe needs a little MORE water? Just guesses.