Hi, I have a Chinese Pistachio tree in my yard which I planted 4 years ago and is 2.5m tall. Every autumn it fails miserably to produce any color at all. It goes from dark green in summer to dark green with a VAGUE hint of burgundy in autumn and then drops its leaves. There are many other Chinese Pistachio trees in the neighborhood that color superbly. Will this problem get better with age or am I stuck with a poor specimen. The tree gets morning shade all summer, then full sun the rest of the day. It is being slightly protected by a larger tree right next to it. The autumn temps regularly get down to 3 degrees celcius overnight.
Any advise/experiences would be helpful, Thanks