We finished harvesting the primocane bearing raspberries in grow bags on October 31 for the trial funded by the USDA Specialty Crop Block Grant Program. We noted symptoms of a disorder on the Polka variety, but not on the other varieties in the trial (Josephine, Crimson Giant, Himbo Top, and Joan J.)
Dr. Courtney Weber, Associate Professor and Small Fruits Breeder at Cornell University – NYSAES was consulted about this problem and he mentioned that he had seen this before and it was fairly typical on the Polka variety later in the season. It may possibly be the natural senescence pattern of Polka leaves and does not seem to affect the long term performance of the plantings.