Winter damage to boxwoods

Asked June 27, 2019, 2:15 PM EDT

15 yr old Boxwood hedge suffered winter damage in Minneapolis. Seeing significant dead, brown leaves. We’ve pruned back dead branches. Wondering if this hedge will recover ever? If so, how long will it take to recover? How should we protect the hedge for another winter? Should we fertilize this summer?

Hennepin County Minnesota boxwood

1 Response

Thanks for the question about your boxwood. It is one of my favorite shrubs. Sometimes I think that it doesn’t get the recognition that it deserves.

You indicated that you pruned back the dead branches. Yet, the pics still show some dead branches. Perhaps you took the pics before the pruning? In any event, be sure to remove all dead branches down to the ground. They will not produce any new foliage. I am encouraged by the new growth coming up from the base. This indicates that the shrub is not dead. It is very likely that things will recover to some extent this season. However, it may not attain its former shape immediately. This may take another season or two. Here are two sites that will provide information regarding winter burn and how you might prevent a recurrence of events during the upcoming 2019-2020 winter:

https://extension.umn.edu/planting-and-growing-guides/protecting-trees-and-shrubs-winter

https://www.extension.iastate.edu/news/2009/may/060801.html

There is a blight (fungal disease) that can infect boxwood and cause browning of leaves. This is a possibility for your boxwood. But if this was the case, I would not expect to see the vigorous, new growth at the base. Yet this is something to consider should you see additional leaf browning. If this occurs, please get back to us. Here is some information about this blight:

https://apps.extension.umn.edu/garden/diagnose/plant/deciduous/boxwood/leavestantobrown.html

Once all dead branches have been removed, be sure to keep things well watered. This will encourage additional vegetative growth. Adding fertilizer now should be done. Do not delay this too long. It will be most effective when the boxwood is showing vigorous growth. Use a fertilizer that has a high nitrogen content. 10-10-10 garden fertilizer would be a good choice. It should be available at any garden center or big-box store. Water it in well.

Here is another site that might provide you further information about your boxwood (several links are available at the site)

https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/yellow-or-brown-boxwoods.htm

I would refrain from doing any extensive pruning at this time other than minor shaping. Here is a site that contains great information about pruning boxwoods:

https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/trimming-boxwood-bushes.htm

Good luck!!