Regrowth

Regrowth is a new mechanic in Don't Starve Together. There are three main mechanisms for regrowth, which work slightly differently: Regrowth, Offspring Regrowth , and Desolation Regrowth. On the World Customization Screen, the regrowth setting sets a multiplier on how quickly each of these regrowths happen. For all types of regrowth, it only decreases the timer for the regrowth time while that entity is in its regrowth season. For example, desolation regrowth time for blue mushtrees is 50 days, and their season is winter, so it will only try to spawn once every 3.33 winters.

Regrowth
After one of these entities is destroyed, the game will try to place another one after the regrowth time has passed. It will try somewhere in a 5-tile radius of where they were originally; if it tried to place the entity too close to another entity, within 5 tiles of a base structure or wall, or if a player is within 16 tiles, it will try again after the regrowth time has passed once more.

Note that although flowers do not regrow during the rain, new flowers still spawn during rain like they do in single-player Reign of Giants.

Offspring Regrowth
This is intended to give the effect of forests growing and reclaiming land. Each tree has a timer after which it will try to spawn a sapling of the same type nearby. If there are fewer than 5 other trees of the same type in the radius that would have 5 such trees at worldgen, then it will succeed in spawning one.

Desolation Regrowth
Desolation regrowth is intended to spawn trees in areas they belong in after the area has has all or almost all of its trees destroyed, such as by an out of control forest fire. Desolation regrowth cannot occur if there are any of the same type of tree within a 10-tile radius, and base structures or walls within 5 tiles, or any entities at all within a tile.