Keys for Seeding High Yielding Wheat

Wheat can be successfully established and grown using many planting methods, but several management practices can certainly enhance your potential for growing a productive grain crop this season. Those practices include timely planting, appropriate seeding rates and methods, suitable seedbed preparation and fall weed control.

Planting wheat early is very tempting, but can considerably hamper wheat grain productivity due to multiple issues that may arise in our mild southern climate. This completely contradicts the logic associated with planting most summer crops early, such as corn and soybeans. However, wheat is a winter crop that only needs to emerge and begin tillering before becoming dormant during the winter. Records from the Kentucky Wheat Production Contest (where winners typically produce more than 100 bushels per acre) rarely show top yields resulting from plantings prior to the recommended dates. Planting wheat early needlessly exposes it to developmental, fertility, weed and numerous pest problems which ultimately limit yield potential. Our mild southern winters can further intensify this issue, because the onset and degree of wheat dormancy may vary considerably from year to year. The adverse effects from excessive fall growth include spring freeze injury, development of Barley yellow dwarf virus, Hessian fly and armyworm infestation, more disease infection, more weed competition, poor nutrient use, and increased lodging. Growers in many regions of Mississippi have experienced severe freeze injury during recent seasons and ensuing yield loss generally increases drastically with early-maturing wheat. Thus, we need to carefully manage variety maturity and planting date, as both these factors affect wheat maturity. Early-maturing varieties should be planted later than normal, to avoid excessive development, which could expose them to substantial freeze damage in the spring. Conversely, late-maturing wheat varieties should be planted before early varieties. We should also plant multiple varieties differing in maturity, to spread risk, since seasonal temperatures also influence maturity.

Our suggested wheat planting dates (within 10-14 days of the average first fall freeze date) should provide warm enough temperatures and long enough days for seedling emergence and tillering to begin before dormancy occurs. This can vary considerably depending upon seasonal temperatures, but normally corresponds to:

North & Central Mississippi:             October 15 -November 10

Delta Region:                                     October 20 – November 15

South Mississippi:                             November 1 – November 25

Coastal Region:                                 November 15 – December 10

Although wheat and other small grains may be successfully established using various rudimentary broadcast planting methods, I generally recommend planting your grain crop with a drill, in order to optimize stand establishment, seeding vigor and survival.  By planting wheat with a grain drill using sound management techniques, you can use more conservative  seeding rates without reducing wheat productivity. Our normal planting recommendation is to strive to establish 1.0 to 1.3 million wheat plants/acre or 23 to 30 plants/ft.² While it is important to strive for specific planting standards, wheat does have outstanding capability to compensate for wide variation of plant density. In other words, wheat research from the Mid-South generally shows a very flat response to seeding rate over a wide range, particularly higher than the suggested guidelines. Thus, an acceptable final stand of small grains can be as low as 50% of the establishment goal of 1.0-1.3 million plants per acre (500,000 plants per acre or 11 per sq. ft.). However, wheat seed size can range from 11,000 to 18,000 seeds per pound (should be noted on the tag), so you should base seeding rate on the number of seeds (seeds per pound), rather than on the volume or weight of the seeds (bushels per acre). This may help your pocketbook somewhat, particularly if you use an insecticide seed treatment. Only a few situations justify using higher than normal seeding rates (10-20%), including no-tillage into high residue or extremely late plantings, for adequate stand establishment.

Some have asked about broadcast-planting on raised beds (primarily to facilitate irrigation of the subsequent double-crop), and this method can be productive given adequate drainage. However, the appropriate seeding rate for broadcasting and incorporating seed is considerably higher (40-45 seeds/ft.²), because emergence success will likely be modest (60-70% of planted seed). If you broadcast small grain seed on the soil surface without subsequent incorporation (such as aerial seeding of muddy fields), you should generally utilize very high seeding rates (50-60 seeds/ft²), because emergence and seedling survival can be relatively low (around 50% of planted seed).

Given normal fall showers, both summer and winter weeds may be present in many fields. It is essential to kill weeds before planting wheat.  A burndown herbicide applied prior to planting and/or before crop emergence is absolutely necessary to eliminate weed competition during emergence and early tillering stages, particularly in a no-tillage system. Tillage may also serve the same purpose in conventionally prepared seedbeds.  In fact, tillage may be the most practical option to control volunteer Roundup Ready corn prior to planting wheat. Maintaining a weed-free environment during planting and stand establishment is essential because weeds are very competitive with young wheat plants, particularly if they emerge before or at the same time as the wheat crop. Likewise, don’t fall into the assumption that wheat weed control is easy and can wait till springtime. This is where we often leave a lot of wheat yield potential on the table. Abundant populations of quick-starting weeds, including henbit and annual bluegrass, may intensely compete with wheat for over 100 days, if left unimpeded until the spring. Several herbicide options are available which can provide residual weed control during the fall. If you would like more assistance, feel free to contact myself or any of our MSU Extension Service Crops Team.