Turf Tips

Turf 101: Why does a November application of fertilizer work?

Nitrogen stimulates increased photosynthesis and the extra energy derived from this goes directly into growth, respiration to maintain the plant (similar to humans), or into storage. In early November, the temperature is still adequate for photosynthesis, but cool enough to minimize respiration demands and too cold for significant growth. Therefore, most of the extra energy derived from a November application of nitrogen is stored by the plant and not used for any type of growth (including root growth) until the following spring. Next spring, these storage products are used in green-up of the plant and more importantly, for root growth. According to some of our earlier research, it is important for the plant to take up the nitrogen quickly in the fall and store the energy for maximum root growth next spring with a minimum of shoot growth. Though one might think that nitrogen applied early next spring would do the equivalent as November-applied nitrogen, just the opposite occurs and shoot growth is stimulated dramatically with early spring-applied nitrogen. A spring application of nitrogen will never compensate for a missed application in November.

Zac Reicher, Professor/Turfgrass Extension Specialist

Send corrections, suggestions, and comments to biehlj@purdue.edu