I have several seed production plants that I spray weekly, from early spring until they are gone in the fall. After I pick the berries, I hate spraying them but I don't want blight getting started in there either. I am thinking of just cutting them down and removing the tops, I know they will be back next spring but I don't want to do anything to weaken the plant or get less berries next year from doing this. The plants are still green and very healthy, so I am sure none of the tops juices have gone back to the root.