Don’t sweat it if your corn isn’t planted by May Day!
How often have you heard the old rule of thumb that you lose a bushel a day for every day corn is planted after May 1?
Roger Elmore and Jenny Rees at the University of Nebraska want to dispel that myth.
The agronomists reviewed research from the universities of Nebraska, Illinois, Purdue, and Kansas State. Tthe Kansas State work was based on National Corn Growers corn yield contest winners from 2011 to 2016.)
After compressing all the data and reviewing the yields results, Elmore and Rees came to the conclusion that there “is a “planting window” within which yields are often very similar. That window exists between mid- to late-April and mid-May. After this period, “yields decrease rapidly.”
In addition to planting data, a number of other factors have a major impact on corn stand and yield. They include:
- Soil temperature and moisture. These are the major factors affecting stand establishment. Early in the planting window, wait for a forecast calling for at least a 48-hour window of soil temperatures 50°F. and above.
- Take advantage of 48-hour windows when soil temperatures are 50°F. and above so your farm-wide corn field planting dates fall between mid-April and mid-May.
- Keep an eye on soil temperatures by checking the ground just after dawn using a kitchen or meat thermometer. Schedule planting based on that temperature and the weather forecast for next 48 hours.
- Don’t worry if your corn is not planted by May Day. Plant as soon as conditions permit. Late-May and early-June plantings can, in some years, produce well, depending on the rest of the growing season.
- Avoid mudding corn in wet fields. You can lose more yield from planting in wet fields than you gain from early planting.
“Planting date management is not about the date you plant your FIRST field, rather it is about when you can plant your LAST field!” Elmore and Rees add. “If you wait until soil temperatures are projected to be above 50°F. for the rest of the planting season, you will likely be planting your first field later than the beginning of the optimum period and thus need more rain-free periods afterward to get the rest of your fields planted.”