Plants maintain growth through meristems

Unlike animals where cell divisions that lead to making the organism are often limited to a short window in time, plants need to make new cells all the time to produce more organs like roots and shoots. This is part of their "replace and rengenerate" strategy that is needed to survive damage from the environemnt when you can't simply run away. These sites of permanent "embryonic" cell divisions are called meristems and have a major impact on how plants grow and survive.