DataXu StackAdapt

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

Is 98G Renters Lime?

Is 98G Renters Lime?

Education Yes, but not just renters lime It is true that 98G pelletized limestone is a good fit on rented ground because of its rapid reactivity. Tenant growers can put in place a soil pH maintenance program that calls for lower application rates spread more...

Don’t Short Canola on Sulfur

Don’t Short Canola on Sulfur

Education Increasing acres of canola in the U.S. Canola is a crop that has historically been grown in Canada with a good bit of the production in the province of Alberta. In recent years, states in the high plains of the U.S., such as North Dakota, are starting to...

Wednesday Webinar Series in September

Wednesday Webinar Series in September

Education Andrew Hoiberg, our VP of Research and Development, is hosting weekly webinars this month. These webinars are focused on the benefits of 98G and SO4 and how to implement them into a grower’s fertilizer program. The webinars will take place from 8:30 a.m. –...

Stay in the Loop

By signing up for a seasonal newsletter, you will receive the latest information and news from Calcium Products.


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

Follow Us

Thank you! Your subscription has been confirmed. You'll hear from us soon.