Grass does not “need” to be mowed … it tolerates it. Mowing is always a stress on the plant at any time of year. Defoliation of the grass plant by mowing reduces the amount of photosynthesis that can occur, thereby reducing the amount of carbohydrates (food) that is produced. Reducing the amount of food produced by the plant also reduces the root density and depth. The net effect of removing tissue by mowing is to starve the plant.
The lower the mowing height the greater the stress. Higher mowing heights promote root growth and lead to a healthier plant. Prior to dormancy, it is important for the plant to produce and store as much food as possible for it to survive the harsh winter. A weak plant is more susceptible to winter damage.
And that is why we raise mowing heights (particularly on greens) in October of each year. More leaf tissue … means more food … means a healthier plant … means reducing the risk of winter injury.
Today we substantially raised the mowing heights on greens.
