The rate of grass growth varies depending on the species of grass and external factors such as weather conditions and the type of soil, but most grasses grow an average of 2 to 6 inches each month. Grasses generally fall into two main categories, which are warm season grasses and cool season grasses. Cool season grasses typically begin growing during the cooler months of the year and have slowed growth rates in the late spring and summer, while warm season grasses emerge in the spring and reach their maximum heights during the warm summer months.
Although grasses grow an average of 2 to 6 inches each month, there is variation in their growth rates depending on the availability of water, nutrients and even the presence or absence of insects and grazing animals. Geographical location also influences growth rates and patterns, and grasses of both varieties that live in nutrient-rich soils typically grow at faster rates than grasses seeded in soils of lesser quality. Grasses, like many types of plants, contain various parts, such as leaves, stems and roots, that can also grow at different rates. Heavily grazed grasses, for instance, may have root systems that grow and develop more quickly than the section of plant above the soil surface, which is constantly trimmed and chewed by cattle and livestock. Most grass shoots sprout in the springtime in mild climates when temperatures range between 65 and 75 degrees Fahrenheit. Grasses continue to grow through the spring because of adequate moisture and ideal temperatures and then slow in growth rate during summer when temperatures exceed 75 degrees Fahrenheit and there is less moisture in the air.