Fertilizing Wheat

Soil fertility may be one of the most important factors influencing wheat production.  Proper pH, fertilizer amounts, and timing can have a huge impact on wheat yield and quality.  To properly manage fertility in wheat we need to have recent soil samples, anticipated yield goal, and crop history for the field.Typical yields in our area of 40 – 70 bushels of wheat per acre will require between 80 and 100 pounds of nitrogen (N) per acre.  Early N applications are critical prior to the onset of winter to produce high quality tillers.  As a general rule we use these figures for N applications following summer row crops:

Fall tillers are important because they usually produce more grain than spring tillers.  However, we don’t want to overfertilize because that can result in a greater chance of cold injury.

Nitrogen demand will be low in the winter but as the plants move toward stem elongation demand increases rapidly.  To determine if split N applications would be beneficial, you should take tiller counts at growth stage 25 (full tiller).  This is usually late January in our area.  Randomly sample several spots in the field to determine tillers per square foot.  If tiller counts are low (50 – 60) you should apply approximately 60 pounds of N.  If tiller counts are around 80 you only need 25 – 30 pounds of N, and anything over 110 tillers per square foot requires no additional nitrogen until stem elongation.

Splitting N applications prior to stem elongation can also help reduce N losses on sandy soils and in seasons with excessive rainfall.

To determine final nitrogen needs of the crop it is beneficial to take a tissue sample.  Once you have the results there is a nice chart developed by NC State that gives final N recommendations based off of tissue sample nitrogen levels. You can also find the chart in the UGA Wheat Production Guide

Since these methods for determining N fertility require a little more management, you can contact your County Agent to assist you and help interpret results.