Potassium Fertilizer Basics — Potash, K₂O, and 2026 Pricing Guide

Potassium is one of the three major crop nutrients (N-P-K) and the one with the most stable pricing environment in 2026. Potash (muriate of potash, MOP, 0-0-60) is at $310–$380/ton — the best-priced major input on the board. Here is what you need to know to use it well.

Potassium Products and Pricing

Product	Analysis	K₂O Content	2026 Price	$/lb K₂O
Muriate of Potash (MOP)	0-0-60 or 0-0-62	60–62%	$310–$380/ton	$0.25–$0.32/lb K₂O
Sulfate of Potash (SOP)	0-0-50 + S	50%	$650–$800/ton	$0.65–$0.80/lb K₂O
Potassium-magnesium sulfate (K-Mag)	0-0-22 + Mg + S	22%	$450–$550/ton	$1.02–$1.25/lb K₂O

MOP is the right choice for most row crops: The chloride in MOP (muriate = chloride salt) has no negative effect on corn, soybeans, wheat, or sorghum at standard application rates. SOP's premium (2–3x the price per lb K₂O) is only justified for chloride-sensitive specialty crops like tobacco, potatoes, and some fruits and vegetables.

How to Interpret Soil Test K

Soil Test K (ppm)	CEC Range	Interpretation	Recommendation
<80 ppm	All	Very Low — deficient	Apply 2x crop removal to build
80–120 ppm	Low CEC (<10)	Low	Apply 1.5–2x crop removal
120–180 ppm	Medium CEC	Adequate	Apply at crop removal rate
180–250 ppm	Medium-high CEC	High	Apply below crop removal; drawdown
>250 ppm	All	Very High	No K fertilizer needed

Potassium Crop Removal Rates

Corn grain: 0.24 lbs K₂O per bushel (200 bu/acre = 48 lbs K₂O/acre in grain)
Soybean grain: 1.17 lbs K₂O per bushel (50 bu/acre = 58.5 lbs K₂O/acre)
Note: Both crops remove significantly more K in stover/straw than grain — if stover is harvested or grazed, add those removal figures

Why Potash Is the Best Buy in 2026

Potash is the most favorably priced major nutrient in the current market for three reasons:

Canadian expansion: Nutrien and Mosaic increased Saskatchewan production capacity, providing buffer supply against global disruptions
No China export restrictions: Unlike phosphate and nitrogen, potash is not subject to current Chinese export controls
Sanction substitution: Canadian production has largely offset the loss of Belarusian potash from Western sanctions

The one risk: Brazil's soy crop drives the largest global potash buying cycle in Q3–Q4. When Brazil buys, global prices tighten. Fall 2026 pre-buying at current prices is a sound strategy.

Frequently Asked Questions

What is the difference between potash and K₂O?

Potash is the trade name for the fertilizer product (muriate of potash, 0-0-60). K₂O is the chemical expression used to measure potassium content in all fertilizer analyses — the "K" in N-P-K. A bag labeled 0-0-60 contains 60% K₂O. The actual element potassium (K) is 83% of K₂O by weight, but agronomists use K₂O as the standard unit.

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Potassium Fertilizer Basics — Potash Guide for Row Crop Farmers