Wheat growers in Mississippi have been anxiously watching their fields in anticipation of the growth burst that we have grown accustomed to in recent years. This change in growth that we refer to as the “spring greenup” has been slow in coming in many fields this year, especially those that are located on bottomland where water tends to linger following heavy rains.
Wheat responds to many factors, but the most important variable that is influenced by weather is drainage. Farmers commonly say that wheat does not like “wet feet.” Those of us from the Extension Service who work with farmers stress the importance of drainage in wheat, but invariably many of the fields planted to wheat have areas where drainage is not good.
When the soil is saturated, plants do not produce good roots, and nitrogen applied in the ammonium form like urea cannot be converted to the nitrate form that is needed by plants. As a short-term fix, we sometimes suggest that ammonium sulfate be applied. This product contains nitrogen in the ammonium form, combined with sulfur in the sulfate form. We have found that we get a quicker greenup when this form of nitrogen is applied to most crops, and this is especially true for wheat.
Most of the wheat in this area is finally beginning to get going, or you might say get “growing,” and only the latest planted and wettest fields are still behind schedule. Farmers have had a tough time getting fertilizers and herbicides applied this year, but the last few clear days have given them a change to get caught up on some of these vital chores.
Even though wheat is planted in our area in the fall it really does not (usually) do much growing until spring. With the preferred planting time from mid-November into early December, wheat does not have much chance to grow. Wheat that is planted for grain (rather than for grazing) is planted this late in order to prevent the lush growth that makes the crop more susceptible to winter damage, and the later planting dates allow the crop to delay heading until after most of the late spring freezes that usually arrive around Easter.
Ideally, we want wheat to be healthy, develop abundant tillers that will produce heads later, and allow us to regulate its development with well-timed applications of nitrogen in the spring. We really like to see it remain fairly small until the second application of nitrogen that is usually done about this time of year when plants change from the vegetative phase to the reproductive phase. Some aggressive growers may elect to make a later small application of nitrogen when wheat is in the early boot stage in order to support head formation and seed development.
Within another three weeks some of our wheat fields will be producing the tall stems on which the heads will be formed. We should already be scouting wheat for diseases and insects, but the most important period for scouting comes when the heads are being formed, the stage we call the “flag leaf.”
We have enjoyed some very good spring weather for wheat in recent years, but this year has not been favorable to wheat in general. Our yields may be reduced a little, but with good management from now until harvest we can still come in with a fine wheat crop. Appearance of wheat sometimes deceives people into not giving the crop the things it needs, but this is usually a mistake.If you have a decent stand, give wheat what it needs and it will reward you with good yield.