Our approximately 40 metre long Boxwood hedge has turned to a yellowish orange. I have been told that it needs lime, a treatment that would be done in Spring and Fall. However, this treatment seems expensive for a hedge that may be doomed. Can 2 Lime treatments per year really revive Boxwood?
These often discolor. What to do depends on why, exactly your planting has discolored - do not apply anything without first acquiring a good idea of what the problem is. http://pnwhandbooks.org/plantdisease/host-disease-descriptions/b?title=boxwood
