Posted 28 October 2014. PMN Crop News.
How Late Can we Plant Wheat?
Source: Michigan State University Press Release. msue.anr.msu.edu
East Lansing, Michigan (October 16, 2014)--Usually, the optimum time to plant wheat is several days following an area’s hessian-fly-free date. For much of Michigan, this means that most of the crop would ideally be planted by the first of October. This is often difficult, especially in seasons such as this year, 2014, where the current crop is slow to mature. According to the “Michigan Crop Condition” from the USDA National Agricultural Statistics Service, during the fall of 2013 and 2014, approximately only 20 percent of the crop was sown during the month of September.
Generally speaking, the yield potential of wheat slips approximately one bushel per acre for every day planting is delayed beyond the target window (approximately 10 days following the fly-free-date). This relationship becomes muddled as planting dates stretch beyond mid-October because weather conditions start to play a greater role.
How late a wheat crop can be planted is really a question of how much risk a grower is willing to take. If a grower expects to have the crop insured, then the answer is straightforward because Oct. 25 is the last planting date for crop insurance eligibility. For those trying to estimate the odds of achieving a reasonable yield, it’s important to recognize that the challenge to late wheat is not only the inherent constraints on grain yield, but also its greater susceptibility to winter injury.
That being said, growers have repeatedly demonstrated that late planted wheat can produce very respectable yields. Generally, these successes have benefited from good soil conditions at planting and favorable growing conditions several days following planting. Some farmers find that successful late plantings can achieve yields that are 80 percent of timely planted fields.
So far, wheat planted in mid-October should be faring well thanks to warm soil temperatures that are predicted to continue for the next several days. In contrast, fall 2013 saw temperatures plummet after the first 10 days of October, resulting in significant delays in emergence and little seedling growth before the onset of winter dormancy.
For those electing to plant wheat in late October, or even early November, Michigan State University Extension reminds growers that it is important that the seeding rate be increased to some 2 to 2.2 million seeds per acre (28 to 32 seeds per foot of row). It is also helpful to increase the use of fertilizer nitrogen at planting to 20 to 40 pounds per acre. Even if soil temperatures delay or prevent seedling emergence this fall, the crop will be vernalized, and it will likely emerge in the spring barring a harsh winter.