Overwintering buds of blackcurrant cultivars 'Ben Lomond' and 'Ben More' were examined by differential thermal analysis (DTA). Photographic evidence relates the first (primary) exotherm to the freezing of water in the basal pith and bud scales. The number of secondary exotherms either matched, or was fewer than, the number of floral racemes within the bud. There is evidence in the structure of the secondary exotherms that the freezing of individual primordia was being recorded.