We live on Rockland Road off Uniontown Road on ten acres. We have beautiful boxwoods around the house. A professional pruner comes to our house from time to time and suggested that we inquire about the need to do preventive spraying for boxwood blight. He said that he is not aware of blight in our area and our account representative at Bartlett Tree Experts said the same thing. The spraying would be preventive.The pruner said that I should ask you what you think.
Carroll County Maryland
We do not recommend a preventative spray for the boxwoods unless the boxwoods have been diagnosed with boxwood blight. Make sure the boxwoods do not have boxwood blight. Here is our page for photos and symptoms. Boxwood blight can be introduced by bringing in affected boxwoods and/or contaminated tools, equipment, and other items. https://extension.umd.edu/hgic/topics/boxwood-blight
Since you have a pruner coming on site you may want to think about leaving the tools on site so boxwood blight is not brought in. There is information on the publication from Virginia Tech on Best Mgmt Practices including avoiding boxwood blight, tool sanitizers, etc. https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/PPWS/PPWS-29/PPWS-29-pdf.pdf