Des Moines, Iowa, USA
April 29, 2013

Nitrogen (N) fertilizer applied as anhydrous ammonia, UAN solutions or urea can be lost if adverse (primarily wet) weather conditions precede the uptake by crops. According to DuPont Pioneer, controlled-release nitrogen fertilizers can reduce these losses by delaying the initial release of N and providing it gradually to better match its availability with crop uptake needs.

Controlled-release, also called slow-release or delayed-release, N fertilizers include coated ureas, non-coated "chemical-release" forms and other products. The higher cost of controlled-release products generally excludes their use in cases where conventional N fertilizers can perform the same function adequately. These products may be most useful for:

• High-value crops (i.e. seed crop)
• Environmentally sensitive areas
• Fields highly susceptible to N losses
• Fields with limited opportunities for repeat applications
• Contest plots
• Foliar applications

Most growers of commodity row crops who use controlled-release products likely apply most of their crops’ N needs with conventional products and only use controlled-release products to supplement their primary N fertilization program.

For more information about controlled-release nitrogen fertilizers, view DuPont Pioneer Crop Insights online.

Website: http://www.pioneer.com

Published: April 29, 2013