Actually when any perennial plants begin to look shabby, straggly, open in the center, or it fail to produce is normal amount of blooms, it simple means it is time to divide them. A lot of perennial plants will reach this point at different times, though depending on their root structures and growing habits. The perennial Bergenia plant may actually bloom and grow beautifully for a number of years, then suddenly stop performing. This could be because the plant is choking itself out and may needs to be divided or because something in its environment changed and the plants needs to be moved. To learn how to divide bergenia visit https://www.flowerpeek.com/2023/10/how-to-divide-bergenia.html