February 2018

Aspire® Soybean Fertility


Evaluate the yield response of soybeans to Aspire® (0-0-58-0.5B), MOP (0-0-60) + Granular B (0-0-0- 14.3B) blend and a Control (No K) treatment.


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

  • Micronutrients such as boron (B) are essential for plant growth, yet often overlooked in balanced crop nutrition.

  • Granular B products can be blended with K, but application of these blends leads to undesirable B distribution.

  • Additionally, boron is mobile in the soil and can leach beyond root systems under certain conditions.

  • Aspire® is a premium potash that uses Nutriform® technology to combine potash along with two forms of boron (fast and slow release) in every granule. This combination delivers B for uptake throughout the season, and provides a more flexible application window compared to other B sources.


Crop: Soybean (Glycine max)

Years: 2016–2017

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

Experimental Design: Small-plot RCBD with 4 replications.

Cropping Conditions:

P Rate: 40 lbs P₂O₅/ac applied as MicroEssentials® S10® across entire trial

K Rate: 60 lbs K₂O/ac applied as MOP or Aspire®

B Rate: 0.5 lb B/ac applied as Granular B or Aspire®

Application Timing: Preplant

Application Method: Broadcast incorporated


Soybean Yield


  • Soybean yields increased with the addition of potassium and boron.

  • The addition of MOP + Granular B increased yields by 1.8 bu/ac.

  • Aspire® demonstrated a +2.0 bu/ac response over the MOP + Granular B and a +3.8 bu/ac response over the Control (No K).

  • This study demonstrated that when a foundational rate of phosphorus and sulfur is provided by MicroEssentials® S10®, additional yield can be achieved with potassium and boron applications; especially with Aspire® and Nutriform® technology.

©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.