02 Oct Good winter wheat stands still possible when planting late
With good rainfall in many areas and the highest price for winter wheat in some time, there is an increased interest in seeding winter wheat this fall.
If you’re seeding winter wheat after harvesting a crop in the fall, it’s likely that you’re planting after the suggested dates for seeding. Other factors, such as rainfall and trying to destroy a stand of downy brome or jointed goatgrass, can delay seeding. Several changes can be made to help compensate for the delayed seeding.
Late seeding is usually classified as at least a week after the suggested date. Usually, yields start to decline if planting is more than a week late. But in some situations, it may even outyield winter wheat planted earlier, especially if wheat was planted much before the suggested dates. This can be attributed to disease and insect problems and the use of extra soil water in the fall.
Use narrow row spacings
When planting after the recommended date, narrower row spacings of five to eight inches are preferred over 10- to 15-inch row spacings. If you use a wider spacing, such as from using a 15-inch planter, consider seeding twice with the second pass at a slight angle to the first. Use one-half the seeding rate each time. This works only with disc drills, as hoe drills move a lot of soil and bury much of the seed from the first pass.
Increase the seeding rate
Late seeding usually results in less root and tiller development. A general recommendation is to increase the seeding rate 10 to 15 pounds (150,000-225,000 seeds) per acre per week after the suggested seeding date for your area. The maximum seeding rate for rainfed wheat is 120 pounds (1.8 million seeds) per acre or limit the maximum to about twice the seeding rate used for seeding at the suggested date for your area.
For irrigated wheat the recommended seeding rate is 90 pounds (1.35 million seeds) per acre if planted at the suggested seeding date. Increase the seeding rate 15 to 20 pounds (225,000-300,000 seeds) per acre for every week after the suggested seeding date to a maximum of 180 pounds (2.7 million seeds) per acre.
Also, when no-tilling wheat into row crop stubble, seeding rates are usually increased by as much as 50% even when seeded up to 10 days before the suggested seeding date. When planting occurs more than one week after the suggested seeding date, the seeding rate should be 90 to 120 pounds (1.35 to 1.8 million seeds) per acre for rainfed. With irrigated wheat, increase the seeding rate the same up to the maximum listed earlier.
Apply phosphorus with the seed
When seeding wheat late, phosphorus placed with the seed helps improve yield. Use 20 pounds phosphorus where none is called for by soil tests and increase other phosphorus rates which are over 20 pounds by 20% for late seeded winter wheat.
The normal superphosphates and ammonium phosphates generally have a negligible effect on wheat stands because of the low salt content of phosphorus fertilizers compared to nitrogen fertilizer, the low concentration associated with narrow rows (five to 12 inches), and the generally high rates of seed used. The seeding mechanism for applying phosphorus fertilizer with the seed is not critical unless the producer applies additional nitrogen at the same time. Do not apply more than 15 to 20 pounds of nitrogen per acre with the seed. Also, do not use 12-0-0-26.