Sulfate of Potash Crop Fertilizer | Protassium+®

About Protassium+

Essential Nutrients

Protassium+® is a dual nutrient source that delivers high potassium and sulfate sulfur with virtually no chloride and low salt index. It is the premium K source that helps plants reach their full yield potential. 

High Potassium

High Potassium

With an equivalent potassium content of 50 percent potassium oxide (K2O), commonly referred to as potash, Protassium+ provides the vital K plants need to resist drought, disease and promote healthy growth, yield, and harvest quality.

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High Sulfur

Often referred to as the fourth macronutrient, sulfur helps support plant functions that can affect yield, quality and marketability. Recent sulfur deficiencies point to the need to replenish the nutrient to help encourage more profitable results.

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Low Chloride

Many crop, turf and ornamental plants are particularly sensitive to chloride and salt. Continued application of potassium sources with a high chloride content or salt index can have a toxic effect, building up in the soil and contributing to lower yields, lower quality, poorer appearance and lost income.

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Low Salt

Protassium+ has the lowest salt index per unit of K2O of all major potassium sources. For this reason, Protassium+ minimizes the risk of soil toxicity for added peace of mind and flexibility in application.

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Organic Products

Naturally Produced

Compass Minerals Ogden Inc.® utilizes natural,  sustainable and environmentally responsible processes to produce a line of Protassium+ products suitable for organic farming.

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Protassium+ VS. MOP

How to Compare K Sources

When comparing potassium sources, some of the factors to consider include K content, value-added nutrients, risks in over-application, application costs, yield performance and overall quality.

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Industry Activity

Our Partnerships

Compass Minerals is very active in the plant nutrition industry. We fundamentally understand the importance of having an active voice with stakeholders and influencers in the agricultural market. Many of our team members hold leadership positions on boards and participate in conferences, tradeshows, and other meetings that connect and provide a platform for discussions. Here is a listing of just a few membership organizations Compass Minerals is involved in and are members of:

The Fertilizer Institute (TFI)

Fertilizer Canada

California Association of Pest Control Advisors (CAPCA)


Premium Nutrients

About Us

Compass Minerals is the largest producer of sulfate of potash (Protassium+) in North America. We are dedicated to supplying growers, crop consultants and retail partners with valuable plant nutrition insights, information and research to support exceptional growing operations.

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