Orange tree issue

Hello everyone,

I was hoping someone could help me identify what maybe wrong with my orange tree. It has been planted for about a year. The tree was doing great up until the last few weeks. The leaves have started to curl and fall off. I haven't had any luck pin pointing a problem. Hope one of y'all can help.

 

Maybe your ambient temperatures are fluctuating too much? Citruses like constant warm temperature.

 

What would be considered too much of a temperature deviation?

 

More, than your orange can tolerate.