Vineyard Underground

Organic grape production is gaining momentum, but making the transition from conventional farming requires careful planning, patience, and a willingness to adapt. In this episode of Vineyard Underground, Fritz welcomes Rob Warren, owner and operator of Desert Willow Vineyard and Warren Farms in Seminole, Texas, to share his experience converting his vineyard to certified organic production.
Rob explains how his agricultural background in organic row crops gave him experience with organic systems long before he applied those principles to grape growing. As consumer demand began to shift toward more natural and sustainably produced wines, wineries started seeking organic fruit, prompting Rob to pursue certification.
During the conversation, Fritz and Rob walk through the realities of transitioning a vineyard to organic management. Rob discusses the three-year certification timeline, the importance of documenting the final use of conventional inputs, and the need for growers to rethink pest, disease, and weed management strategies.
A major focus of the episode is that Rob uses sheep in the vineyard. The sheep help control weeds, provide natural fertilization, and even assist with canopy management by removing leaves in the fruiting zone.
Throughout the episode, Rob provides honest background information on the challenges and the long-term benefits of improved soil health and stronger vine resilience.
For vineyard owners considering organic production, this episode offers practical guidance and real-world lessons from a grower who has successfully made the switch.
In this episode, you will hear:
Market demand from wineries and consumers increasingly favors organic grape production

Weed management is often the biggest early challenge when moving away from conventional herbicides

Sheep can play a valuable role in weed control, fertilization, and canopy leaf removal

Organic pest and disease control often requires more frequent monitoring and spray applications

Soil health improvements through cover crops and livestock integration strengthen long-term vineyard resilience

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 live, virtual two‑day Early Season Vineyard Management Bootcamp on April 22nd and 23rd.
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:
Rob Warren is the owner and operator of Desert Willow Vineyard and Warren Farms in Seminole, Texas, and a leading innovator in regenerative and organic vineyard management and farming. 
Connect with Rob:
Facebook: https://www.facebook.com/desertwillowvineyard 

Instagram: https://www.instagram.com/desertwillowvineyard/ 

YouTube: https://www.youtube.com/channel/UCrjWaulJw7tATQC3trzhPJQ 

Episode Sponsor:
Today's episode was brought to you by Clemens Technologies and Sunridge Nurseries.
Thank you to Clemens Technologies for sponsoring today's episode. Clemens Technologies is the market leader in machinery for all elements of vineyard management. Visit https://www.clemens-online.com/us/ and provide the code UNDERGROUND to receive 5% off your order of in-stock machinery. Or reach out to Thomas Clemens directly at [email protected] with any questions.
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.
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 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.