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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

Meet Maria!

Meet Maria!

EducationMeet Maria Meyer, our R&D and sales intern for this summer. Maria is a Senior at Iowa State University majoring in animal science with a minor in general business. She grew up in Okoboji, Iowa and has spent the last few summers working and living in Ames....

Meet Dena Resech!

Meet Dena Resech!

EducationWe would like to announce the hiring of Dena Resech! Dena graduated from the University of Wisconsin-River Falls with a bachelor’s degree in Horticulture in 2009. Dena is bringing 12 years of agronomy experience to our team with strengths in agronomy sales...

98G For Topdress Application

98G For Topdress Application

EducationStarts to work in a few weeks; will get benefits in same growing season even with later application98G works quickly, much quicker than ag lime. This is due to its high purity (94% CCE) and small particle size (90% or more thru 100-mesh screen). This means it...

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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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