Viticulture – Vineyard Soil Health Session

Eleonora Cataldo* | Pamela Lippi | Giovan Battista Mattii

Clinoptilolite-Enriched Soil Amendments Improve Vine Water Status and Phenolic Balance under Warm and Dry Conditions

Eleonora Cataldo,* Pamela Lippi, and Giovan Battista Mattii

*University of Florence, Viale delle Idee 30, Sesto Fiorentino (FI) 50019, Italy, eleonora.cataldo@unifi.it

Climate change is increasingly challenging viticulture by intensifying heat waves and water deficits, which often leads to unbalanced ripening and reduced phenolic quality in red cultivars. In Sangiovese, excessive exposure to high temperature and radiation may also enhance flavonol accumulation, including quercetin derivatives, potentially affecting wine stability. Sustainable soil management strategies based on circular economy principles may help mitigate these constraints while valorizing winery by-products. A 2-yr field experiment was conducted in a Sangiovese vineyard in central Italy to assess the effects of innovative soil amendments on vine ecophysiology and berry composition. Three soil treatments were compared: a new land conditioner obtained from composted winery residues enriched with clinoptilolite (ZW; 30 t/ha); natural zeolite (Z; 10 t/ha); and organic compost (C; 20 t/ha). Seasonal measurements included single-leaf gas exchange, midday stem water potential, leaf temperature, chlorophyll fluorescence, and extrinsic water-use efficiency. At key ripening stages and at harvest, yield components, technological maturity, yeast assimilable nitrogen, and detailed phenolic profiling (anthocyanins, hydroxycinnamic acids, flavonols, and quercetin derivatives) were determined. Across both seasons, ZW and Z improved vine physiological performance more than compost, showing higher photosynthesis, less negative water potential, lower leaf temperature, and higher photochemical efficiency. These physiological benefits were associated with enhanced berry phenolic quality, including increased anthocyanin accumulation and reduced accumulation of quercetin derivatives. Compost-treated vines generally exhibited lower performance and higher quercetin levels during ripening and at harvest. By-product compost with clinoptilolite-based soil management represents a promising, climate-resilient strategy to improve vine water relations and phenolic balance in Sangiovese, while supporting circular approaches through the recovery of winery wastes.

Funding Support: No funding

Long-Term Under-Vine Grass Cover Alters Root-Soil-Microbe Interactions Without Persistent Root Avoidance

Michela Centinari,* Suzanne Fleishman, Lily Cao, Taran Rowles, Francesco Pelusi, David Eissenstat, and Terrence Bell

*Penn State University, 218 Tyson Building, 417 Eisenhower Rd, University Park, PA, 16802, mzc22@psu.edu

Increased plant diversity through vineyard floor management is widely promoted to enhance soil health and agroecosystem resilience, yet concerns persist regarding belowground competition between grapevines and under-vine cover crops. In eastern North American vineyards, perennial grasses such as creeping red fescue (Festuca rubra) are used or considered as under-vine management options to moderate vegetative growth and reduce reliance on herbicides; however, their long-term effects on grapevine root systems and root-associated microbial communities remain poorly understood. We synthesized results from a series of multiyear field studies conducted in a high-resource vineyard in Pennsylvania to evaluate belowground responses to long-term (>9 yr) under-vine grass cover. Using complementary approaches–including soil coring, deep root observation boxes, and root interaction assays–we assessed grapevine root distribution and morphology, soil resource availability, and rhizosphere microbial composition, with particular emphasis on soil depth and nutrient context. Across years, under-vine grass altered soil resource dynamics and microbial community composition in a depth-dependent manner, with stronger responses in fungal communities and minimal effects on overall microbial diversity. These microbiome shifts were most pronounced in shallow soils and under nutrient-limited conditions. In contrast to earlier observations in younger vineyards, long-term grass adoption did not result in persistent shallow root avoidance or reductions in fine root length density or root diameter, suggesting functional acclimation of grapevine root systems over time. Together, these findings indicate that long-term under-vine grass cover can influence belowground ecological processes without imposing sustained belowground stress on mature grapevines in high-resource systems. This integrative perspective provides a foundation for region-specific vineyard floor management recommendations that balance vine growth control with long-term soil health.

Funding Support: USDA-NIFA; Pennsylvania Department of Agriculture (Wine Marketing and Research Board)

Soil Hydraulic and Thermal Responses to Combined Regenerative Management Practices in a Commercial Sonoma Vineyard

Axel Herrera,* Ian Ferrer, Kelsey Fenn, Mallika Nocco, Elisabeth Forrestel, Nicolas Bambach, and Cristina Lazcano

*University of California, Davis, One Shields Avenue, Plant and Environmental Sciences building, office 3310., Davis, CA, 95616, axherrera@ucdavis.edu

Regenerative practices such as reduced tillage, organic amendments, and managed grazing are promoted in vineyards for their potential to support soil health and drought resilience. Yet, the effects of these practices on soil water dynamics in commercial settings are not well understood. To address this gap, we are monitoring soil hydrology in a field experiment in Sonoma County, CA, where cover cropping is used across all management systems. The study compares one conventional treatment with alternate-row tillage (CT) and two regenerative treatments that combine compost and sheep grazing: one managed as no-till (RN) and the other with alternate-row tillage (RT). Since spring 2023, hourly soil moisture and temperature at 30, 60, and 90 cm in both vine and tractor rows have been monitored. Continuous sensor monitoring focuses on three primary treatments: the conventional system, the regenerative no-till system, and the regenerative alternate-till system. In parallel, seasonal infiltration tests were conducted using mini-disk infiltrometers across the treatments, and cumulative infiltration was modeled using the Philip equation to estimate infiltration parameters. Preliminary results show that treatment-level differences in infiltration have been small, with most variation occurring between years rather than among different treatments or management regimes. Continuous soil moisture and temperature records exhibit expected seasonal patterns, with only modest and inconsistent separation among treatments. In some periods, regenerative treatments show slightly higher mid-profile moisture, though these differences remain subtle relative to temporal variability. Ongoing work centers on event-based analyses (heatwaves and major rainfall) and the integration of weather station data, evapotranspiration estimates, and soil physical properties such as aggregate stability. These integrations and analyses will help refine the interpretation of whether stacked regenerative practices provide measurable hydrologic benefits relevant to irrigation planning and climate adaptation.

Funding Support: Foundation for Food & Agriculture Research (FFAR) and the California Department of Food and Agriculture (CDFA)

Long-Term Under-Vine Creeping Red Fescue: Water and Nitrogen Ddynamics in an Eastern US Vineyard

Taran Rowles, Charles White, Suzanne Fleishman, Don Smith, Hailey Frontino, Francesco Pelusi, and Michela Centinari*

*Penn State University, 218 Tyson Building, University Park, PA, 16802, mzc22@psu.edu

Perennial under-vine cover crops are a sustainable alternative to herbicide strips that can improve soil health and reduce erosion in vineyards. In the eastern United States, perennial grasses, including creeping red fescue, can also moderate excessive vegetative growth by altering key soil processes such as soil water and nitrogen (N) availability. As a result, growers may need to adjust water and nutrient management in vineyards with under-vine grasses. However, the long-term effects of under-vine grasses on N and water availability remains poorly understood. In this study, we evaluated the long-term (9 yr) effects of under-vine creeping red fescue on soil water and N dynamics in a Pennsylvania Noiret (Vitis hybrid) vineyard grafted on two rootstocks with different vigor potential. We leveraged multiyear soil measurements with field and laboratory assessments conducted in 2025. Soil moisture data, from 2019 to 2025 (3 to 9 yr after creeping red fescue was established), showed consistently greater water availability and storage at shallow soil depth (20 cm) compared with under-vine herbicide across growing seasons. Higher soil saturated hydraulic conductivity and lower soil bulk density (15-cm depth) indicated greater soil porosity and water infiltration in creeping red fescue plots, contributing to the increased water availability. Despite differences measured in previous years, leaf petiole N concentration at veraison did not differ between grapevines with and without under-vine creeping red fescue in 2025, following 7 yr without fertilizer application. Furthermore, soil under creeping red fescue maintained higher inorganic N concentrations throughout much of the 2025 growing season. Laboratory soil incubations also indicated greater potential for soil N mineralization in these soils. Together, these findings combined with vineyard production metrics provide a framework for developing long-term nutrient and water management recommendations for vineyards adopting under-vine grasses, such as creeping red fescue.

Funding Support: Penn State College of Agricultural Science, USDA-NIFA

10:25 am – 10:45 am	Clinoptilolite-Enriched Soil Amendments Improve Vine Water Status and Phenolic Balance under Warm and Dry Conditions Eleonora Cataldo, University of Florence, Italy
10:45 am – 11:05 am	Long-term Under-vine Grass Cover Alters Root–soil–microbe Interactions Without Persistent Root Avoidance Michela Centinari, The Pennsylvania State University, University Park
11:05 am – 11:25 am	Soil Hydraulic and Thermal Responses to Combined Regenerative Management Practices in a Commercial Sonoma Vineyard Axel Herrera, University of California, Davis
11:25 am – 11:45 am	Long-term Under-vine Creeping Red Rescue: Water and Nitrogen Dynamics in an Eastern United States Vineyard Taran Rowles, The Pennsylvania State University, University Park

Viticulture – Vineyard Soil Health Session

Research Reports

Moderator:

Speakers:

Share This Page