The general guideline for fertilizer application is to apply fertilizer when the turf is actively growing, therefore, the timing will be different for warm and cool season species. Cool-season species are most actively growing during the spring and fall of the year. However, high spring fertility treatments may be detrimental to the survival of the turf through the high stress periods of mid-summer. The general recommendation would be to apply 0.5 to 0.75 pound Nitrogen/1,000 ft² in March/April and May/June and one pound Nitrogen/1,000 ft² in August and September and again in the late fall. Total nitrogen applications to cool season turf in temperate regions will generally range from three to five pounds N/1,000 ft² per year.
The general recommendation for warm season turf species is 1 pound nitrogen/1,000 ft² per growing month. This is only a guideline. On heavier soils in drier conditions this will be too much. On sandy soils during periods of heavy rainfall, this will not be enough.