|A few of my boxwoods are turning a bronze color and then dying. Others beside them are fine. Someone suggested that my soil lacked iron. Do you have any suggestions?|
|I don't believe that iron is the problem. Your boxwoods are suffering from a root-related stress. I could be that a drought stress or soggy soil has brought on the problem. However the cause is probably one of two root attacking organisms: nematode damage to the roots, or a fungal root wilt disease. Neither is something that you can control or cure. You should not replant boxwood in that location if it is one of these two culprits.|
To find out for sure which it is, dig a plant in the last stages of decline (don't wait until it is completely dead) and examine the stem and roots. The fungal disease appears as dark brown/black streaks between the bark and inner wood when you slice down the stem lengthwise with a knife. Nematodes appear as swollen areas of the roots.
Depending on what you find you can make a good choice in selecting replacement shrub species for that area.