Show Notes
Leading microbial ecologist from UC San Diego, Dr. Jack Gilbert joins us to talk about how soil and management decisions shape the vine and wine microbiome. We start by defining what a microbiome is in plain vineyard terms, and Dr. Gilbert explains how vines "select" specific microbes from the surrounding soil to support nutrient uptake, stress tolerance, and overall vine health. We then walk through Dr. Gilbert's Merlot study that showed roughly 95% of the vine microbiome originates from the soil, and we discuss how these early microbial reactions can influence wine character before commercial yeast ever goes in. The conversation then turns to real-world vineyard practices. We cover how herbicides, tillage, compaction, and inputs can suppress or reshape soil biology. Listeners also hear about emerging work at the UCSD Soil Health Center, including using soil "prebiotics" and "probiotics" together and developing digital twins of vineyards to time interventions more precisely. In this episode, you will hear: Vines actively recruit microbes from the soil to support health, nutrient uptake, and stress tolerance
Around 95% of the grapevine microbiome can be traced back to the soil where the vine is planted
Early-stage fermentation on the fruit is influenced by native microbes, which can affect wine aroma and flavor
Herbicides, pesticides, and heavy soil disturbance can suppress beneficial microbes and reduce soil function for years
Building soil biology with organic matter, thoughtful inputs, and microbiome-aware practices can improve vine resilience and fruit quality
Follow and Review: If you enjoyed this episode, be sure to follow the podcast and leave a 5-star review on Apple Podcasts! Your support helps us reach more listeners. 💜 Click the '+' in the top right corner of Apple Podcasts to follow now. Resources: Register for Fritz's FREE live virtual post-harvest learning event - Vineyard Rx: Post-Harvest Diagnostics and Action Plans on October 7th at 6:00 PM Central. Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button. Today's Guest: Dr. Jack A. Gilbert is a world-renowned pioneer in microbial ecology who holds joint professorships at the University of California San Diego's Department of Pediatrics and the Scripps Institution of Oceanography. As the co-founder of the Earth Microbiome Project and author of Dirt is Good, his landmark research has been pivotal in proving that soil acts as the primary living reservoir for the grapevine microbiome, fundamentally shaping wine fermentation and character. Connect with Jack and view his research at: UC San Diego Soil Health Center - https://soilhealthcenter.ucsd.edu/
The Gilbert Lab at UCSD - https://gilbertlab.ucsd.edu/
Get his book, Dirt Is Good: The Advantage of Germs for Your Child's Developing Immune System - https://a.co/d/0iYBP4Sq Episode Sponsor: Today's episode was brought to you by Sunridge Nurseries and SensorInsight. Thank you to Sunridge Nurseries for sponsoring today's episode. Sunridge Nurseries is the exclusive nursery sponsor of the Vineyard Underground podcast. They have been a family-owned company for over 45 years, and their dedicated focus on quality and consistency has grown them into the largest supplier of grapevines in both North and South America and the industry leader in nursery standards. Visit them today at SunridgeNurseries.com and mention the code Underground to receive a podcast listener discount on your vine order. Thank you to SensorInsight for sponsoring today's episode. SensorInsight is a leader in vineyard soil moisture and weather monitoring. SensorInsight designs state-of-the-art, remote satellite monitoring of soil moisture and weather, bringing actionable information for your vineyard operations straight to your phone, with real-time data so you can best decide when to turn on your irrigation, how long to run the system, and learn how the dynamics of soil moisture can ch
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