Horticulture Chair, Carol Giunta, warns us all to take a look at our the underside of Viburnum bush leaves as they emerge this month. Soon it will be time to spray for the Viburnum Leaf Beatle to prevent defoliation down the road. “Spray when larvae first appear in early May for best results. If damage from adults is excessive, a second application in mid-to late summer may be helpful. Insecticidal soap is not effective against adults.” See the full document from Cornell University here.
