The periderm plays a crucial role in trees, acting as a barrier protecting internal tissues against biotic and abiotic stresses, thus having an impact on tree physiology, ecology, and general performance. It consists of the meristematic phellogen, whose activity gives rise to suberized phellem (cork) cells outwardly and the parenchymatous phelloderm inwardly. Despite the periderm importance, intra-annual and seasonal changes in phellogen activity and phellem and phelloderm differentiation are poorly recognized. Therefore, we aimed to compare periderm development and functioning in successive years in horse chestnut, utilizing standard histological methods. We distinguished six stages of periderm development, including phellogen initiation and the differentiation of its derivatives. In the following years, the phellogen was active for a similar period, but produced fewer derivative cells. Importantly, some phellogen cells lost their meristematic characteristics before the end of the season and differentiated into phellem. To maintain periderm integrity, the remaining phelloderm cells underwent divisions, leading to phellogen re-initiation. Alternatively, when all periderm cells differentiated into the phellem, the new (subsidiary) phellogen originated from the underneath collenchyma. We postulate that phellogen re-initiation could be a mechanism ensuring the functional integrity of the periderm and discuss the role of phelloderm or collenchyma cells in this process.