Fuji apple keeps having yellow leaves
I live in Sana Ana, southern California and just planted this Fuji apple 3 weeks ago. Look like it has not been growing well since then. The leaves, starting from the bottom section of the tree has been turning into yellow and falling off looking like this . The green leaves also look a little bit withered. It almost did not rain much this time of the year so I don't know if it's over-watering related or some type of other thing. Any help would be great!