Silver Queen' has creamy edges.
All varieties can revert to dark green leaves.
If branches appear with dark green leaves, prune them immediately. There are very few problems with this plant where I live in Santa Maria on the Central Coast. Powdery mildew is such a problem in Sacramento that the Parks Department no longer uses it. Mildew is hard to control, and it seems to like hot summers. This is an excellent landscape plant in areas where mildew is not a problem.