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Maximize Soil Fertility

Powerful Results & Committed Customer Support

At Calcium Products, we help customers maximize soil fertility to achieve higher crop yields by offering the highest quality calcium-based fertilizers on the market. With a focus on strong customer relationships, continuous improvement, and leveraging technology, we strive to help our customers reach their full potential.

Our products, 98G pelletized limestone and SO4 pelletized gypsum, are manufactured in Iowa, atop some of the purest limestone and gypsum deposits in the world. Though a majority of our product is used in the agriculture industry, we also manufacture smaller grade sizes for the professional turf industry.

98G is pelletized limestone – the most effective and consistent product to correct and maintain soil pH.

SO4 is pelletized gypsum – the superior sulfur source that delivers the right amount of sulfur, perfectly matching plant needs.

Correct & Maintain Soil pH With 98G

Are you making soil pH a priority in your fertility program? Soil pH is critical to healthy plant growth and works as a master variable in the soil, governing chemical and biological processes. Don’t just correct your pH when you soil test, maintain it at a level to maximize your yield every year.

Increase Your Crop Yield With SO4

SO4 supplies a strong initial release of sulfur followed by a steady supply throughout the growing season, perfectly matching plant needs. Averaged over 67 trials across the Midwest, SO4 increases corn yield by 15.4 bushels/acre compared to no sulfur.

Meet the Calcium Products Team

From a highly experienced executive team to our skilled territory sales managers and everyone in between, we are committed to providing our customers with the products, information, and support they need to be successful.

Locate a Dealer Near You

With an ever-expanding list of capable dealers spread across the United States, find your nearest Calcium Products dealer to learn more about how our products can work for you.

Grow Your Soil Fertility Knowledge

The Case for Soil pH Maintenance

The Case for Soil pH Maintenance

Education Don’t just correct soil pH, maintain itSoil pH is the foundation for nutrient availability. Correction of soil pH is difficult to consistently achieve because it is affected by challenging weather or field conditions, as well as availability of appropriate...

Comparing SO4 and Elemental Sulfur

Comparing SO4 and Elemental Sulfur

Education Sulfur AvailabilityWhen evaluating sulfur sources, one factor to account for is what form the sulfur is in. A common sulfur fertilizer used in the fall is elemental sulfur (ES), which exists in the elemental form, meaning it must be converted to the...

Leverage SO4’s Application Flexibility

Leverage SO4’s Application Flexibility

Education Capitalize on SO4’s VersatilitySO4 pelletized gypsum is a versatile and flexible sulfur fertilizer, which makes it a convenient sulfur source for ag retailers to inventory in storage and growers to use on-farm. SO4 can not only be used on any crop, it is...

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(800) 255-8196 Customer Service
ISU Research Park, 2520 N Loop Dr, #7100
Ames, IA 50010 Corporate Address

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