February 2015

Aspire® Cotton Sidedress Study


Evaluate the yield response of cotton to various preplant applications of potassium (K) and boron (B) sources: [1] MOP (0-0-60), [2] MOP + Granular B, [3] Aspire® (0-0-58-0.5B) compared to preplant + sidedress applications of K + Granular B.


  • Preplant applications of MOP are a common practice in cotton production. Additionally, many growers add B to their preplant and sidedress blends

  • Cotton requires B in relatively large amounts compared to other plants. If not present, B is the micronutrient most likely to limit cotton production.

  • Boron deficiency in cotton may cause a distorted, stunted terminal, abnormal uppermost leaves and aborted flowers (Fig. A).

  • Aspire® is the first-of-its-kind micronutrientenhanced potash fertilizer. Manufactured using Nutriform® technology, Aspire® premium potash combines K and B in each granule to help achieve uniform nutrient distribution.


Crop: Cotton (Gossypium hirsutum L.)

Years: 2014

Locations: 5 trials across regions of the U.S. (AL, GA, MS, NC, SC) 


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

Experimental Design: Small-plot RCBD with 4 replications.

Cropping Conditions: All trials conformed to local cropping practices.

Total K Applied: 90 lbs K₂O/ac

Total B Applied:

MOP: 0 lb B/ac

Aspire: 0.75 lbs B/ac

Granular B: 1.5 lbs B/ac

Application Method: Broadcast

Application Timing: Preplant (PP) Sidedress (SD)


Cotton Yield by Treatment


  • Cotton yields increased with aEven in situations of split application with 2 times as much B applied (preplant: 60 lbs K₂O/ac + 1.0 lbs B/ac | SD: 30 lbs K₂O/ac + 0.5 lbs B/ac), PP Aspire® (90 lbs K₂O/ac + 0.75 lbs B/ac) increased yield by 101 lbs lint/ac.

  • With only half as much boron applied, the preplant Aspire® application (0.75 lbs B/ac) outyielded the preplant application of MOP + Granular B (1.5 lbs B/ac) by 44 lbs lint/ac.

  • The higher yields with preplant Aspire® compared to other treatments demonstrates the advantages of the uniform nutrient distribution of boron compared to traditional MOP + Granular B blends and split-application methods.

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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.