Answer: I would be particularly concerned about planting boxwoods in a windy site, especially in your cold climate. Boxwoods really do best with protection from winter winds. The wind dries them out and stresses them. The oscillating temperatures we tend to have in spring can also stress them severely, especially those planted in full sun. Stressed plants are more likely to suffer pest and disease problems as well. Boxwoods can be affected by several pests and diseases that could case a single branch or one side of the plant to go offcolor and then die; dog urine can also cause a similar symptom. Another possible cause could be root issues related to poorly drained soil.
I would suggest you consult with your local county extension as to what is affecting the boxwoods you already have before deciding to plant more of them nearby. If you decide to go ahead, I would suggest those with the best winter tolerance in terms of cold hardiness and maintaining a good green coloring so you would want to stay with Korean box types such as Winter Gem. And if you could provide a windbreak, that would be a good thing, too.
Good luck with your boxwoods!
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