Replacing Boxwood


Do you think it is safe to start replacing Boxwood after last year’s blight???


Hello – Boxwood has been plagued with several issues recently.  Boxwood blight has been a problem in Ontario since 2014 while damage from the box tree moth larvae which was first detected in Etobicoke in 2018 has now spread more widely in Toronto and was a major issue for gardeners last year. We have had previous questions about both of these issues.  I’ve included links below to our responses.

In the case of boxwood blight, some experts recommend not replanting boxwood in the same spot in the event that the blight spores are still active in the soil.  However, if care is taken to select more blight resistant varieties and follow the practices outlined in our post then successful replacement is possible.

We anticipate that the box tree moth will still be active in the Toronto area this season.  Landscape Ontario, the association for the horticultural professionals has been very active in monitoring and controlling this pest.  Gardeners were advised to not replace boxwood last year as the box tree moth was so widespread in Toronto.  It is too early to tell how successful last year’s efforts were in controlling this pest.  So I do not advise a spring planting of boxwood – not because of blight but because of the box tree moth.  The box tree moth can have up to three lifecycles each year.  The first larval period is from May 15 to June 15 so that is when we should know whether this pest has been brought under control.  Check back with us then for an update.

March 10, 2021