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The grape berry provides a model for investigating the physiology of non‐climacteric fruits. Increased K⁺ accumulation in the berry has a strong negative impact on fruit acidity (and quality). In maturing berries, we identified a K⁺ channel from the Shaker family, VvK1.2, and two CBL‐interacting protein kinase (CIPK)/calcineurin B‐like calcium sensor (CBL) pairs, VvCIPK04–VvCBL01 and VvCIPK03–VvCBL02, that may control the activity of this channel. VvCBL01 and VvCIPK04 are homologues of Arabidopsis AtCBL1 and AtCIPK23, respectively, which form a complex that controls the activity of the Shaker K⁺ channel AKT1 in Arabidopsis roots. VvK1.2 remained electrically silent when expressed alone in Xenopus oocytes, but gave rise to K⁺ currents when co‐expressed with the pairs VvCIPK03–VvCBL02 or VvCIPK04–VvCBL01, the second pair inducing much larger currents than the first one. Other tested CIPK …