For many corn growers, one of the most difficult decisions to make is when to begin planting each year. If you plant too early, the crop may not pull through the harsh early spring conditions. If you wait, you may not get all of your acres planted on time and suffer yield loss from late planting. This is always a tough call. You take significant risks either way.
Some farmers try to plant in cold, early spring soils to avoid the yield loss associated with late planting and to create additional days for the crop to reach maturity and dry down. But there is potential yield loss related to early planting as well. When seeds germinate in cold soils, they are vulnerable to chilling injury, which impairs their development and may kill them, thus reducing stand counts.
In addition, cold soils in early spring make for lengthy emergence periods, causing uneven stands. This alone can lower yields 8-10%. Prolonged emergence in cold soil temperatures will also slow root development, increasing the risk of disease and insect damage.
All of these factors weaken plant health and reduce stand counts, sometimes bad enough to require replanting.
View a 2003 Early Plant yield comparison.
