BY ALEX RENK
It is common knowledge that planting early, for both corn and soybeans, should in most cases help improve yield. This fact came out in university research conducted decades ago. I was curious on how well this carried over to today so I cross-referenced yield to planting date in our test plot database for each variety. Location and year was disregarded to give a very broad based look.
Below is a graph of RS213NR2. Here you will find that if you wanted to see a yield break the 70 bu/acre mark, you needed to get them planted by May 25th. May 20th if you wanted to see 80 bushel yields and before May 10th if you wanted to crowd 90 bushel.
When you plot the trend line, it works out to be roughly 0.4 bu/acre lost per day of delayed planting. This trend line stayed very consistent across varieties with soybeans losing 0.4 bushels a day and corn losing 1 bushel a day when planting is delayed.
So, should everyone try to get everything planted right away? Yes and no. If you want to maximize yield you need to plant early, within 2 weeks of your earliest planting time. However, early planting can be a boon for certain diseases. In soybeans, White Mold and Sudden Death Syndrome outbreaks tend to be more of an issue in early plantings. If these diseases are prevalent in your area, early planting may be questionable because any yield gain could be wiped out by yield loss from infestation. The good news is you can use ILeVO® seed treatment for SDS. White Mold does not have a decent solution for control yet.
Early planting should deliver more yield based on solid logic. More days of energy absorption for the plant and quicker canopy to keep weed pressure down. This lays the framework for maximum yield.
Other factors can come along and rob that yield from your field such as disease, insects, and drought. Still you can’t plant later and expect to push the yield barrier. Early planting is a big part of the foundation for high yields. By getting in early, you will be setting yourself up for the best results in the fall.