I have some boxwood shrubs that the middle died and the outside of bush is still green. I think that maybe they got frost? Do I prune all the dead stuff off? And what time of year should I do it?
The Gardener’s Answer
Hi, Melanie: When did you notice the middle of your shrubs was not living? You mentioned frost so I am wondering if they were fine going into the winter and then came out of winter looking like they do now. Typically frost damage occurs on the tips of boxwoods and not only in the middle of the plant. As far as pruning you can go ahead and prune out any dead branches now; this should be done as soon as it is apparent to prevent spread of potential disease/insect problems. They should not be pruned to shape this late in the summer. Are these newly planted shrubs or are they older established plants? Have you noticed any insect activity and what does the foliage look like on the rest of the plant? If your boxwoods are new additions they may not be receiving enough moisture. It is essential for all new plantings to have sufficient water given to the root ball of the plant as well as the surrounding area. It is hard to narrow down the problem without knowing specifics but prune out the dead and keep the plants watered but avoid fertilizing this late in the summer since it will encourage new growth, making it much more susceptible to frost damage. Keep an eye on the rest of the plant and if it starts declining take a sample to your local garden center or your county Extension office for analysis.