Experts agree on the importance of liming for climate-resilient agriculture

The important contribution that regular liming makes to soil health and climate resilience was a key takeaway from the first Lime Symposium organized by Vereinigte Kreidewerke Dammann (VKD), an Omya joint venture, in January 2025. Experts from the Universities of Hannover, Kiel and Osnabrück joined agricultural advisors from state institutions and private organizations, as well as from trading partners and agricultural trade advisors to discuss the need for reliable solutions to soil fertility and plant health issues, particularly in the light of increasing challenges caused by climate change.

Acid soils can have a devastating impact on soil structure, nutrient availability and crop productivity, yet many growers continue to suffer their consequences without taking action. According to the 2018 Thünen Report, 42% of arable soils and 57% of grasslands in Germany suffer from excess acidity, which could be alleviated by regular liming. As Dr. Michael Dreyer, CEO of Agro Counseling Dreyer, explained, "An optimal pH improves nutrient uptake and stabilizes soil structure, which enhances production input efficiency, boosts water retention, and supports higher yields and crop quality.”

Prof. Dr. Stephan Peth from Leibniz University Hannover agreed, emphasizing that proper pH is vital for maintaining soil structure. His research, using X-ray tomography, reveals how changes in soil structure are affected by pH adjustments. Dr. Tina Frank, Agroecology and Soil Science expert at the University of Osnabrück joined the discussion, explaining, "Lime promotes the formation of stable soil aggregates, optimizing air and water balance and creating better conditions for soil organisms like earthworms." 

It is the calcium in lime that has such an advantageous effect on soil structure. The calcium ions improve soil flocculation, binding clay particles and organic matter together to form aggregates.  These factors contribute to greater resilience against extreme weather conditions like drought or heavy rainfall. Well-limed soils are less prone to nutrient leaching, especially nitrogen, and are also less susceptible to wind and soil erosion or compaction. 

Prof. Dr. Ute Kropf from Kiel University of Applied Sciences showed that calcium not only benefits the soil but also plant health and productivity. Her long-term trials demonstrated that fields with regular lime applications produced higher yields and healthier crops, especially barley and sugar beets. She explained that calcium contributes to disease resistance through its role in cell wall stability. 

To maximize liming benefits, Kropf offered the following practical tips:

• Incorporate liming regularly into the crop rotation, using stubble lime applications, or by applying lime at the end of winter in areas with high rainfall
• Divide fields into sub-areas for more efficient lime application based on soil sampling
• Choose liming materials carefully, avoiding high-magnesium limes on wet soils
• Test calcium saturation if soil calcium levels appear inadequate
• Monitor soil structure regularly and consider loosening compacted soils.

Liming: Crucial but often overlooked

Despite the known benefits of liming, many farmers neglect it. Experts agreed that the delayed, long-term effects of improper liming, like declining yields, often go unnoticed. Misconceptions also persist, such as assuming that calcium and magnesium fertilization alone can influence pH, without considering the critical role of calcium carbonate, which corrects soil pH as well as providing essential calcium for soil structure and crop nutrition.

The correct use of regular liming was deemed to be an essential element of sustainable agriculture and attendees at the Lime Symposium agreed that it should be included as part of the crop production cycle. Even under challenging climatic conditions, it helps maintain stable yields. Granulated lime, alongside powdered lime, is a valuable tool for precise application using advanced spreaders.  Oliver Borowy, Sales Manager at Omya-VKD, demonstrated the importance of proper lime application by showcasing the flocculation effect in the soil. He also highlighted the differences in reactivity between commercially available lime products, noting that well-adjusted soil can effectively neutralize acid inputs through its buffer function, thus maintaining soil health and ensuring long-term productivity.

Summarizing the event’s conclusions, Rolf Werner, Head of Sales for Agriculture at Omya-VKD, said, "It is crucial to develop solutions today to maintain soil fertility for future generations. Liming is one of those inputs that has a marked impact on soil health, which is the foundation for successful farming and long-term food security. It was clear from our first Lime Symposium that experts agree that regular liming is key to solving climate change challenges and improving the resilience of agricultural crop production.” 

The next Lime Symposium will take place in January 2026. For details and to register your interest, click here.