I have 4 Cheyenne Privets and about 3 weeks ago they started not looking good. Many of the leaves on the bottom 2/3 of the plant have yellowed and fallen off. The newest growth at the top is still green and healthy looking. The leaves aren't brown or dry or curled, just like a variegated yellow and green look (but its not supposed to be variegated). Any ideas what the cause could be? I don't want to lose these because they are just starting to provide some privacy. Any help is greatly appreciated. Thanks!
-John