Insights from a Year of Regenerative Agriculture Data Highlights the Practices that Optimize Better Farming Practices and Inform Trials
Towards the end of 2024 Agrology hosted a special end-of-year webinar to share key insights from the data gathered throughout 2024. The webinar highlighted a year of soil health data, demonstrating the actionable insights growers employed this year to optimize their farming practices and foster sustainability.
Leading growers including Sonoma County Winegrowers, Redwood Empire Vineyard Management, The Donum Estate, Joseph Phelps Vineyards, Grigich Hills Estates, Vino Farms, O’Neill Vintners & Distillers, and a handful of others that wished to remain anonymous, permitted us to share the key findings that emerged from their 2024 trials.
Agrology defines regenerative agriculture as the better alignment of agriculture management with ecosystem function and soil health. This shift in thinking requires that we all share learnings and ideas. As we kick off the new year, we hope that sharing these stories will help inspire growers to set up their own trials to evaluate ecosystem function and soil health on their ranches. That said, while regenerative principles, learnings and ideas can and should be broadly applied and discussed, the specific systems, practices and knowledge on a specific farm should be developed by/with farmers and their own contexts.
Tillage Practices: Striking the Right Balance
In 2024, Agrology partnered with Redwood Empire Vineyard Management, Sonoma County Winegrowers and Wilbur Ellis to compare no-till, every-other-row till, and full-till practices in the Sonoma Winegrowers’ Farm of the Future project. The findings showed nearly-immediate improvements in water holding, reduced soil evaporation, and less extreme temperatures in the soil and vineyard canopy. These benefits are often associated with no-till systems in CA vineyards, but we were surprised that the improvements here were expressed and measured in the first year of the trial.
Beyond water and temperature, tillage can also negatively impact soil structure and aggregate, leading to a long-term loss of microbial biomass and activity. However in the short term, tillage can actually often increase soil respiration by incorporating more oxygen and soil organic matter into the rhizosphere. This creates a “feast then rest” cycle in soils, which appears as a burst of CO2 respiration following tillage. Sometimes this means that when transitioning to no-till or reduced tillage, soils respire less than they did when they were tilled. In this trial, we saw nearly no decline in soil respiration in blocks that adopted no-till or reduced-tillage practices, which for us signifies a big win.
In summary, the first year of results in this trial support the hypothesis that reduced tillage immediately improved water conservation, soil and canopy temperature in the vineyard and had no negative impacts on microbial respiration. This trial will continue in 2025, and we are excited to see if improvements in the water cycle, soil temperature, and soil structure start to improve soil respiration compared to conventional tillage.
The same results were measured in a similar tillage trial at Donum Estate, where reduced tillage has been in place since 2020.
Cover Cropping: The Root Buffet Effect
Diverse cover crops were found to enhance soil microbial activity by providing a “root buffet”—a variety of different types of root exudates (liquid energy such as amino acids, organic acids, sugars, enzymes and proteins) that feed the soil microbiome. A standout trial involving Merced rye showed its ability to stimulate microbial activity due to its extensive root structure. We always emphasize the importance of diversity in cover cropping to support a resilient and functional soil microbiome, but this specific trial was comparing single species. The Merced Rye performed the best, stimulating the largest increase in soil microbial activity due to its extensive root structures. A single rye plant has over 13 million root branches, with a combined total of over 390 miles of roots and 7000 miles of root hairs. These root hairs are where exudates are exchanged for plant-available nutrients along the surface of the root hairs, an area known as the rhizosphere.
Water Management: Maximizing Efficiency
Various tillage trials in Sonoma County revealed that no-till systems retained soil moisture more effectively, reducing irrigation needs. Continuous monitoring demonstrated how water infiltration and retention were significantly improved in no-till blocks compared to full-till ones. Maintaining soil structure through no-till practices not only conserves water but also enhances the ability for crops to be resilient to drought and heat stress, particularly in water-scarce regions.
Grazing vs. Herbicides: A Comparative Study
At Joseph Phelps Vineyards, Agrology supported a study comparing sheep grazing to herbicide use for terminating cover crops. We found that the sheep stimulated more microbial activity, whereas herbicides had a residual negative impact. This is likely due to the fact that there are certain enzymes within sheep saliva that actually produce a hormonal shift in plants, producing a larger flush of root exudates. This increases microbial activity (which we monitor via continuous soil respiration) and that drives increased nutrient cycling, which allows the plants to recover from the grazing event. In addition, the manure that the sheep leave behind is full of nutrients, organic matter, and microbial inoculants which help boost the metabolism of the soil food web. All of these factors contribute to the positive ecological and soil health impacts of sheep grazing vs. herbicide use as a termination strategy for cover crops.
Compost Teas: Timing is Everything
A compost tea trial at Grgich Hills demonstrated the importance of timing biological amendments. Applications during the early spring, when soil microbial activity was naturally high, yielded the best results. Compost tea significantly increased microbial respiration, highlighting its potential as a cost-effective soil health booster. Growers can maximize the impact of biological inputs by aligning applications with natural peaks in microbial activity during spring and fall, which were clearly seen across a wide variety of data sets that the Agrology team shared in this webinar.
Measuring Success: Beyond Traditional Metrics
Agrology’s continuous monitoring revealed that traditional metrics like total organic carbon (TOC) or soil organic matter (SOM) only tell part of the story. Continuous data provided insights into the dynamic, ever changing nature of the soil carbon and nutrient cycles and its interplay with microbial activity. By adopting dynamic monitoring systems to understand and optimize soil health in real-time, growers are ensuring that regenerative practices yield both operational and environmental benefits.
Unlike traditional lab-based methods which measure potential microbial activity under controlled laboratory (artificial) conditions, Agrology’s system provides continuous insights in real-world conditions of real-world fields and vineyards. One of the key findings this year from Agrology data was that microbial activity thrives in the “Goldilocks zone” of soil temperature (65–85°F) and moisture. Practices like no-till and cover cropping help maintain these optimal conditions, enabling consistent microbial activity and better nutrient cycling.
Building Resilient Farming Systems
2024 insights underscore the critical role of data in advancing regenerative agriculture. From tillage strategies to cover cropping and biological amendments, the practices tracked and analyzed by Agrology have equipped farmers with the tools to enhance soil health, improve water use efficiency, and build resilience against climate challenges.
As we look to 2025, the lessons from this year pave the way for more informed decision making, ensuring that regenerative agriculture continues to thrive as a solution for sustainable farming and climate resilience.
Interested in more? Access our webinar for the full content.