A Purdue Extension publication offers farmers tips on phosphorus applications by focusing on four simple principles.
The publication, Tips for Environmentally Friendly Phosphorus Applications in Indiana, is intended to help farmers better understand how and when to apply phosphorus fertilizers to their fields in a way that isn’t damaging to the environment.
“The fast and simple approach, such as broadcast P fertilizer application, is not the best approach environmentally,” says co-author Tony Vyn. “The dissolved P in all P fertilizers is water soluble and can become an environmental hazard under certain weather conditions following application to the soil surface with no incorporation.”
The tips correspond to the “4R Principles,” which are specific to Corn Belt cropping systems of differing tillage and crop rotations:
- Right rate: Apply the correct rate of P fertilizers; test your soil, and only apply fertilizer where it’s needed.
- Right source: Understand the amount of phosphorus that is in the fertilizer and account for the other nutrients it contains.
- Right time: Applying P fertilizer at the wrong time can be detrimental to water quality, so avoid applying it just before a heavy rain is expected and consider split applications and immediate incorporation to reduce risks.
- Right placement: Placement choices, such as broadcasting and shallow or deep banding, can affect the environment more than crop yield; tillage practices also can affect placement options.
The publication is available free for download at Purdue Extension’s The Education Store. Search for product number AY-386-W.