February 2017

Aspire® Corn – Fall vs. Spring Balanced Crop Nutrition


Evaluate the yield response of MAP (11-52-0) + Aspire® (0-0-58-0.5B) and MicroEssentials® SZ® (12-40-0-10S-1Zn) + Aspire® applied in the fall and spring compared to MAP alone.


  • H Fall applications of phosphorus (P) and potassium (K) fertilizers may be preferred in certain cropping systems to evenly distribute seasonal workload, but spring applications are also a common practice in the Midwest.

  • MOP is commonly used as a potassium (K) source in soybean production.

  • Research has shown that P and K fertilizers containing micronutrients in a single granule provide improved nutrient distribution and increased crop nutrient uptake compared to conventional fertilizer blends.

  • Aspire® is the first-of-its-kind micronutrient-enhanced potash fertilizer. Manufactured using Nutriform® technology, Aspire premium potash combines K and boron (B) in each granule to help achieve balanced crop nutrition.

  • MicroEssentials® SZ® uses Fusion® technology to fuse four nutrients into one nutritionally balanced granule. This provides uniform nutrient distribution, increased nutrient uptake and season-long sulfur for maximum yield.


Locations and Crop Management:

Crop: Corn (Zea mays)

Years: 2014–2016

Data Source: Field studies conducted by third-party, independent researchers.

Locations: 19 trials across the U.S. and Canada United States – IA, IL, IN, MI, MN, ND, NE, OH, SD Canada – ON

006848-M2205 Aspire Corn AgriFacts k4

Experimental Design: Small-plot RCBD with 4 replications.

Cropping Conditions:

N Rate: Fall treatments received partial nitrogen (N) in the fall to balance for phosphate applications, with the remaining N applied in the spring. (Total N rates were based on local recommendation.)

K Source: Aspire®

K Rate: 60 lbs K2O/ac

P Source: MAP, MicroEssentials® SZ®

P Rate: 80 lbs P₂O₅/ac

Application Timing: Fall or spring preplant

Application Method: Broadcast incorporated


Corn Yield


  • MicroEssentials® SZ® + Aspire® had the highest yield in both fall and spring applications.

  • MAP + Aspire® yields were 6 bu/ac higher than MAP alone for both the fall and spring applications.

  • MicroEssentials® SZ® + Aspire® yields were 12 bu/ac (6.2%) higher than MAP alone with the fall application.

  • MicroEssentials® SZ® + Aspire® yields were 10.4 bu/ac (5.3%) higher than MAP alone with the spring application.

  • Regardless of fall or spring application, a combined application of Aspire® with MicroEssentials® SZ® is a superior technology for balanced crop nutrition and increased yield.

©2020 The Mosaic Company. All rights reserved. AgriFacts, MicroEssentials, SZ, Fusion, Aspire and NutriForm are registered trademarks of The Mosaic Company.

Individual results may vary, and performance may vary from location to location and from year to year. This result may not be an indicator of results you may obtain as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible.

WARNING: Contains boron. Use of boron may result in crop injury. DO NOT place this product in direct contact with the seed.