QUESTION: My rose blooms have dark brown spots around the edges of the petals, but not on the leaves. What is this and how can I get rid of it?ANSWER: That is thrips, which is not an unusual problem this time of year. Thrips are a destructive insect, especially on the buds of light-colored roses. They produce many generations a year. They damage bloom tissue as they feed, which causes the browning.Take off the old blooms, which may harbor eggs, and use a pesticide that states on the label it is effective against thrips on roses. Follow the directions for spacing applications of the insecticide. Most all-purpose rose insecticides contain a chemical that works against thrips.