The price of fertilizer is continuing to climb. With the price of commodities it will be difficult for may to apply less fertilizer fearing a loss of yield. With proper management and knowledge of your soils you may just be able to apply less fertilizer and increase yields. In this memo from Midwest Labs, for customers with higher magnesium and higher CEC soils some options to increase Potassium availability;

Potassium availability, and/or rate of exchange, can be enhanced by one or more of the following:
1. Optimum potassium soil test levels per C.E.C. range and percent magnesium values.
2. K2O fertilizer applied in bands.
    a. Starter
    b. Surface band
    c. Subsurface band
    d. Combination of (a) + (b) or (a) + (c).
3. Improve soil aeration
4. Adequate exchangeable soil calcium.
    a. Calcium increases potassium adsorption into the plant (2).
    b. Use calcitic lime on acid soils excess in magnesium.
    c. Use gypsum where soil pH is greater than 6.4 on soils with excess magnesium.
    d. Calcium additions can help alleviate soil compaction zones and promotes good soil structure

From: SOIL & FERTILIZER MANAGEMENT CONSIDERATIONS FOR SOILS EXCESS IN MAGNESIUM

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