Vineyard Underground

In this final installment of the Vineyard Nutrition Essentials series, Fritz is joined by Dr. Jaclyn Fiola, Assistant Professor of Soil and Environmental Science at Delaware Valley University, to unpack the critical role magnesium plays in vineyard health and productivity. Building on prior discussions around potassium, the conversation explores how magnesium functions as a key macronutrient, particularly as the central component of chlorophyll and a driver of photosynthesis and energy transfer in grapevines. Dr. Fiola explains that magnesium primarily originates from soil minerals, especially in darker, magnesium-rich parent materials, and that soil characteristics such as pH, texture, moisture, and cation exchange capacity influence its availability. There is a delicate balance between magnesium, potassium, and calcium, and nutrient competition can lead to deficiencies even when soil levels appear adequate. Listeners will learn how to identify magnesium deficiency symptoms, including interveinal chlorosis in older leaves, and why these symptoms typically emerge later in the growing season. The episode also underscores the importance of accurate diagnosis through soil and tissue testing to avoid mismanagement. Listen now to learn the important role of magnesium in your vineyard. In this episode, you will hear: Magnesium as a core component of chlorophyll and photosynthesis Soil pH, texture, and moisture driving nutrient availability Competition between magnesium, potassium, and calcium Late-season deficiency symptoms and how to recognize them Importance of tissue testing for accurate diagnosis Pre-plant and in-season magnesium correction strategies 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: Visit www.virtualviticultureacademy.com/sampling to access Fritz's how-to guides and videos for proper sampling and target nutrient values. Listen to Dr. Jaclyn Fiola's previous podcast episode (episode 73) to learn about the role of potassium in vineyards. Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button. Come grow with Fritz through https://www.virtualviticultureacademy.com! Save $75 off your first year of membership with the code Underground at checkout. Today's Guest: Dr. Jaclyn Fiola is a soil scientist who specializes in vineyard soils and soil science pedagogy. She works as an Assistant Professor of Soil and Environmental Science at Delaware Valley University. Connect with Jaclyn, follow her, and view her research. Episode Sponsor: Today's episode was brought to you by Vigneron Toy Store and Shellt Grow Tubes. Thank you to Vigneron Toy Store for sponsoring today's episode. Vigneron Toy Store specializes in Harvesters, Sprayers, Frost Mitigation Equipment, Canopy Management Trimmers, and more. As grape growers themselves, they can expertly help you determine the best equipment for your specific vineyard needs. And, as a special offer for our podcast listeners, you can save 5% off in-stock machines by entering the promo code Underground on the contact form at vignerontoystore.com. Thank you to Shellt Grow Tubes for sponsoring today's episode. Shellt makes the ultimate grow tubes for grape vines and orchard trees. Their grow tubes are reusable, recyclable, and designed to grow with your vineyard by clicking together for taller or wider coverage. I exclusively recommend Shellt Grow Tubes to the growers I work with. Visit https://www.shellt.us/ and order with the code UNDERGROUND to save 15% off all online orders, plus free shipping within the continental United States. Episode Credits If you like this podcast and are thinking of creating your own, consider talking to my producer, Emerald City Productions. They helped me grow and produce the podcast you are listening to right now. Find out more at https://emeraldcitypro.com. Let them know we sent you.

Phosphorus may not grab attention like nitrogen or potassium, but it plays a foundational role in vine growth, fruit set, and overall vineyard performance. In this episode of Vineyard Underground, Fritz welcomes Dr. Terry Bates, Senior Research Associate at Cornell University and Director of the Cornell Lake Erie Research and Extension Lab for Cornell AgriTech, for a deep dive into phosphorus fundamentals. Drawing on decades of research in plant nutrition and root biology, Dr. Bates explains what phosphorus is, where it comes from, and why it is essential for grapevines at the cellular level. From its role in energy transfer and DNA structure to its influence on root growth and fruit development, phosphorus is woven into nearly every aspect of vine physiology. Vineyard owners and operators will walk away with useful guidance on managing phosphorus efficiently while protecting both yield and long-term soil health. In this episode, you will hear: Phosphorus drives energy transfer, root development, and fruit set Soil pH directly impacts phosphorus availability and uptake Mycorrhizal fungi are essential partners in grapevine phosphorus nutrition Excess phosphorus application wastes money and reduces efficiency Tissue sampling helps balance nutrient supply, uptake, and vine demand 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: Visit www.virtualviticultureacademy.com/sampling to access Fritz's how-to guides and videos for proper sampling and target nutrient values. Learn more about Mycorrhizal Fungi in Episode 75 - The Importance of Mycorrhizal Fungi for Vineyard Health with Dr. R. Paul Schreiner. Come grow with Fritz through https://www.virtualviticultureacademy.com! Save $75 off your first year of membership with the code Underground at checkout. Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button. Today's Guest: Dr. Terry Bates is the Senior Research Associate at Cornell University and the Director of the Cornell Lake Erie Research and Extension Lab for Cornell AgriTech. Connect with Terry · Cornell Research & Publications - https://cals.cornell.edu/people/terry-bates · The Efficient Vineyard Project - https://www.efficientvineyard.com/ Episode Sponsor: Today's episode was brought to you by Shellt Grow Tubes and Bahco Tools. Thank you to Shellt Grow Tubes for sponsoring today's episode. Shellt makes the ultimate grow tubes for grape vines and orchard trees. Their grow tubes are reusable, recyclable, and designed to grow with your vineyard by clicking together for taller or wider coverage. I exclusively recommend Shellt Grow Tubes to the growers I work with. Visit https://www.shellt.us/ and order with the code UNDERGROUND to save 15% off all online orders, plus free shipping within the continental United States. Thank you to Bahco Tools for sponsoring today's episode. As innovators for more than 165 years, Bahco has introduced the most advanced tools in the world, and Bahco products are manufactured in factories across Europe. I exclusively prune with the Bahco ERGO™ Bypass Secateurs with Elastomer Coated Fixed Handle (size medium). Visit www.bahco.com/int_en to find a dealer near you to get the best pruning tools on the market, along with loppers, hedging tools, cutting blades, files, and more. Episode Credits If you like this podcast and are thinking of creating your own, consider talking to my producer, Emerald City Productions. They helped me grow and produce the podcast you are listening to right now. Find out more at https://emeraldcitypro.com. Let them know we sent you.

In this first installment of a three-part vineyard nutrition series, Dr. Markus Keller joins us to break down one of the most influential nutrients in vineyard management: nitrogen. We explore from the ground up. Dr. Keller explains what nitrogen is, where it comes from in vineyard soils, and why it plays such a critical role in vine growth, fruit set, and overall vine performance. While nitrogen makes up 78% of the atmosphere, vines rely on soil processes to convert it into plant-available forms like nitrate. Dr. Keller details how nitrogen influences vigor, canopy density, fruit set, berry size, phenolic development, and even wine quality. The episode also dives into how soil type, organic matter, temperature, moisture, and cover crops affect nitrogen availability. For growers across diverse regions, this conversation highlights why vineyard nutrition strategies must be site-specific. Whether you're managing high-vigor blocks or navigating lean soils, episode one of our three-part series equips vineyard owners and operators with foundational knowledge to make smarter nitrogen decisions. In this episode, you will hear: Nitrogen primarily comes from soil organic matter, not rock minerals Microbial activity drives nitrogen availability in vineyards Both deficiency and excess nitrogen can reduce vine balance and fruitfulness Soil moisture and temperature strongly influence nitrogen mineralization Leaf blade tissue sampling offers improved precision for nitrogen analysis 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: Visit www.virtualviticultureacademy.com/sampling to access Fritz's how-to guides and videos for proper sampling and target nutrient values. Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button. Today's Guest: Dr. Markus Keller is a Distinguished Professor in Viticulture at Washington State University, a renowned viticulture researcher, and the author of The Science of Grapevines – a top reference book in the industry. He is also the Project Director for the seven-institution High Resolution Vineyard Nutrient Management Project. Connect with Markus: · Dr. Markus Keller - WSU Research & Publications - https://wine.wsu.edu/faculty/markus-keller/ · High Resolution Vineyard Nutrient Management Project - https://highresvineyardnutrition.com · Order The Science of Grapevines 4th Edition - https://a.co/d/00UpfN1f · Listen to the HiRes Vineyard Nutrition Podcast - https://highresvineyardnutrition.com/podcast/ Episode Sponsor: Today's episode was brought to you by Bahco Tools and Shellt Grow Tubes. Thank you to Bahco Tools for sponsoring today's episode. As innovators for more than 165 years, Bahco has introduced the most advanced tools in the world, and Bahco products are manufactured in factories across Europe. I exclusively prune with the Bahco ERGO™ Bypass Secateurs with Elastomer Coated Fixed Handle (size medium). Visit www.bahco.com/int_en to find a dealer near you to get the best pruning tools on the market, along with loppers, hedging tools, cutting blades, files, and more. Thank you to Shellt Grow Tubes for sponsoring today's episode. Shellt makes the ultimate grow tubes for grape vines and orchard trees. Their grow tubes are reusable, recyclable, and designed to grow with your vineyard by clicking together for taller or wider coverage. I exclusively recommend Shellt Grow Tubes to the growers I work with. Visit https://www.shellt.us/ and order with the code UNDERGROUND to save 15% off all online orders, plus free shipping within the continental United States. Episode Credits If you like this podcast and are thinking of creating your own, consider talking to my producer, Emerald City Productions. They helped me grow and produce the podcast you are listening to right now. Find out more at https://emeraldcitypro.com. Let them know we sent you.

How many incredible grape varieties are hiding in plain sight — simply because they don't fit the modern wine script? We dig into that question in this episode with Jenny and Scott Schultz of Sonoma's Jolie-Laide Wines, a winery built around chasing the unfamiliar and turning "pretty ugly" grapes into seriously compelling wines. We trace how Jenny and Scott's very different paths collided into a shared philosophy: start with great farming, intervene as little as possible, and let each site and vintage tell its own story. For vineyard owners and operators, the conversation opens up a practical discussion about risk, opportunity, and how alternative varieties can make both agronomic and economic sense. We also get inside their cellar to talk about what "minimal intervention" really means — early picking for natural acidity, whole-cluster fermentations, neutral barrels and concrete, and a deliberate refusal to erase vintage character. Even the labels change every year, reinforcing the idea that wine is an agricultural product, not a factory formula. The discussion dives into grapes like Melon de Bourgogne, Trousseau Gris, Scheurebe, and Mondeuse Noir, unpacking how they grow, how they're vinified, and why they deserve a bigger spotlight. It's a conversation about curiosity, craft, and what becomes possible when we stop playing it safe with varieties. In this episode, you will hear: Why Jolie-Laide focuses on rare and overlooked grape varieties Working with growers to graft or plant unconventional grapes Minimal intervention winemaking and whole-cluster fermentations Farming considerations for low-alcohol, high-acid styles Blending, carbonic fermentation, and managing tannin and structure 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: Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button. Come grow with Fritz through https://www.virtualviticultureacademy.com! Save $75 off your first year of membership with the code Underground at checkout. Today's Guest: Jenny and Scott Schultz are the founders and winemakers for the acclaimed Jolie-Laide Winery in Sonoma, California. Connect with Jenny and Scott: https://jolielaidewines.com/ https://www.instagram.com/jolielaidewines https://www.facebook.com/jolielaidewines/ Episode Sponsor: Today's episode was brought to you by Vintner's Vault and Shellt Grow Tubes. Thank you to Vintner's Vault for sponsoring today's episode! Vintner's Vault is the #1 winery equipment company that I recommend to my growers, who are also winemakers. Visit TheVintnerVault.com and use the code UNDERGROUND5 (all caps) to save 5% off of your online order, or mention that you heard about them on the Vineyard Underground podcast when contacting them for a larger piece of equipment, consulting services, or turn-key packages, and they will provide a podcast listener discount for you. Thank you to Shellt Grow Tubes for sponsoring today's episode. Shellt makes the ultimate grow tubes for grape vines and orchard trees. Their grow tubes are reusable, recyclable, and designed to grow with your vineyard by clicking together for taller or wider coverage. I exclusively recommend Shellt Grow Tubes to the growers I work with. Visit https://www.shellt.us/ and order with the code UNDERGROUND to save 15% off all online orders, plus free shipping within the continental United States. Episode Credits If you like this podcast and are thinking of creating your own, consider talking to my producer, Emerald City Productions. They helped me grow and produce the podcast you are listening to right now. Find out more at https://emeraldcitypro.com. Let them know we sent you.

Some of the world's most valuable vineyard lessons are rooted in vines that predate modern viticulture. In this conversation, we are joined by Dr. Laura Catena to explore Argentina's remarkable legacy of old, ungrafted vines and what they reveal about vine genetics, site expression, and long-term resilience. Drawing on her experience, Dr. Catena explains why phylloxera never devastated many Argentine vineyards and how this unique history allowed ancient vine material to survive. The discussion dives into massale selection from old vines, highlighting why genetic diversity matters — especially as vineyard owners contend with climate stress, disease pressure, and the limits of clonal uniformity. We also examine the role of Argentina's high-altitude growing regions and how elevation influences vine physiology, flavor development, and vineyard health. These extreme sites have become a living laboratory for research, helping match plant material to specific conditions and improving long-term vineyard performance. Dr. Catena shares information from the Catena Institute of Wine's ongoing research and how data-driven approaches can elevate both vineyard decisions and wine quality. For growers managing heritage blocks or considering massale selection in new plantings, this episode offers a compelling blend of history, science, and practical guidance — showing how preserving the past can be a powerful strategy for building the vineyards of the future. In this episode, you will hear: Why Argentina has some of the world's oldest ungrafted vineyards The role of massale selection in preserving genetic diversity How old vines contribute to resilience and site expression The impact of altitude and climate on vine health and quality Applying research-driven insights to modern vineyard management 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: Come grow with Fritz through https://www.virtualviticultureacademy.com! Save $75 off your first year of membership with the code Underground at checkout. Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button. Today's Guest: Dr. Laura Catena is a Harvard University graduate with a Medical Doctor degree from Stanford University. She is a fourth-generation Argentine vintner at the award-winning Bodega Catena Zapata, a passionate vineyard researcher, a practicing part-time emergency medicine physician, and an author. And, in 1995, she founded the Catena Institute of Wine with the vision of making Argentine wines that could stand with the best wines in the world. Bodega Catena Zapata: Website - https://catenazapata.com/ Instagram - https://www.instagram.com/catenawines/ YouTube - https://www.youtube.com/CatenaMalbec Catena Institute of Wine: Website - https://www.catenainstitute.com/ X - https://x.com/CatenaScience Dr Laura Catena: Instagram - https://www.instagram.com/lauracatenamd/ LinkedIn - https://www.linkedin.com/in/dr-laura-catena-054987195/ Books - https://www.amazon.com/stores/author/B005H53YWY?ccs_id=4d0248ba-4f00-4c70-b68f-daf91c441439 Episode Sponsor: Today's episode was brought to you by Sunridge Nurseries and Bahco. 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 Bahco Tools for sponsoring today's episode. As innovators for more than 165 years, Bahco has introduced the most advanced tools in the world, and Bahco products are manufactured in factories across Europe. I exclusively prune with the Bahco ERGO™ Bypass Secateurs with Elastomer Coated Fixed Handle (size medium). Visit www.bahco.com/int_en to find a dealer near you to get the best pruning tools on the market, along with loppers, hedging tools, cutting blades, files, and more. Episode Credits If you like this podcast and are thinking of creating your own, consider talking to my producer, Emerald City Productions. They helped me grow and produce the podcast you are listening to right now. Find out more at https://emeraldcitypro.com. Let them know we sent you.