With recent warm weather, winter wheat has broken dormancy and begun to green up. With wheat plants no longer dormant, scouting and management of wheat fields is critical to producing high yields. As discussed earlier in the year, now is the time to plan for N applications where field conditions allow. Below is an excerpt from and a previous newsletter with recommendations for nitrogen application and rates:
Spring applications of N should be made after the plants break dormancy. Although in some situations field conditions may be favorable, nitrogen applied in the late winter before plants have broken dormancy is more likely to be lost before plants can utilize it. Spring N applications should not be made before wheat has broken dormancy and begins to green up. The University of Kentucky publication “A Comprehensive Guide to Wheat Management in Kentucky” recommends: “When making a single N fertilizer application the best time is when the crop growth stage is Feekes 4-5, (Zadoks 30, usually mid-March) just before the first joint appears on the main stem and when wheat starts growing rapidly.” The UK publication goes on to say that “The rate of N fertilizer for a single application should be between 60 and 90 lb N/acre for fields with a yield potential less than 70 bu/acre and 90 to 100 lb N/acre for fields with greater yield potential.”
Wheat plants begin a period of rapid growth and stem elongation once they reach Feekes Stage 6 (first node visible). The plant’s demand for N is high as the stem elongates and rapid growth begins. For optimal use of inputs and to achieve the highest yield potential, spring N should be applied in the period of time following green up prior to stem elongation.