Fall Fertilization and Its Efficiencies
For Luke Lantz, a farmer from Lake Crystal, Minnesota, fall fertilization plans are not a one-size-fits-all program.
“Our fall fertilization depends on what we are doing with our crop,” says Lantz. “If it’s rotation ground going back into corn, we usually apply everything in the fall. If it’s continuous-corn ground, we apply two-thirds of our nitrogen in the fall, along with phosphorus, potassium and micronutrients. Then we apply a preplant nitrogen in the spring to supplement.”
Lantz has compared fall fertilizer applications to spring applications, and doesn’t see any difference in yields. His focus is on the temperature, making sure ground temps fall below 50 degrees to minimize any nitrogen conversion. With a short planting window in the spring, it is difficult to apply all of the fertilizer and plant the fields within that window. Lantz believes placing a baseline of fertilizer down in the fall, and evaluating what needs to be supplemented in the spring, is the most efficient way to provide his crops with needed nutrition.
“Fall fertilization is important, but we want to be good stewards, too,” explains Lantz. “We use nitrogen inhibitors to help stabilize it and keep it in the soil. If we lose nitrogen, not only is that damaging to the water supply, but it’s costly. We are big believers in products that helps us be better stewards of the land.”
After wrapping up a successful harvest, deciding on a fall fertilizer plan is fast approaching. With commodity prices lower than in past years, the decision becomes even more complicated than usual. However, it’s important to remember that with record yields removed from the field this fall, record nutrients were removed from the soil as well. In order to replicate high yields in future years, those nutrients must be replenished.
As part of a fertilizer plan, application timing should be considered. Fertilizing in the spring is likely the best option for farmers working in sandy soils, as it will reduce the likelihood of nutrients leaching before being used by the crops. However, fall fertilizer applications in other types of soil may provide more flexibility in the spring, particularly in light of unpredictable weather in the spring.
Delaying fertilizer applications until the spring comes with some risk. A wet spring may mean late planting and limited time in the field. If other farmers in your area also delay fertilizer applications until the spring, it may be all but impossible for applicators to get fertilizer on all of their fields, as the prime time for application may be a very small window of opportunity.
While in typical Midwest corn and soybean cropping systems there seems to be no agronomic benefits between applying phosphorus and potassium fertilizer in the fall versus spring; the last year has proven how short the planting window can be in some areas due to Mother Nature. For the most flexibility in the spring, consider making your fertilizer investment and application this fall.