Dr. Katie Gold and Dave Combs from Cornell University join Fritz to unpack one of the most confusing topics facing winegrape growers today: how biological fungicides truly fit into a spray program.

Katie explains how the Cornell grape pathology program has expanded rapidly, moving from strictly conventional efficacy trials into extensive work with biologicals as more of these products come out of R&D pipelines. She outlines why growers can't rely on "the next new conventional" anymore and how biologicals are becoming essential tools for sustainable disease management and resistance stewardship.

Dave brings decades of field experience and shares how his initial skepticism about biologicals shifted after seeing modern products perform on highly disease‑prone varieties in one of the toughest vineyards for powdery mildew, downy mildew, black rot, and bunch rots. Together, they walk through what "compatibility" really means and why water pH, formulation, and whether an organism is alive or dead matter far more than many growers realize.

Listeners learn why mixing biologicals and conventionals in the same tank often provides no added control (and may waste money), where negative interactions can show up, and why tightening intervals and understanding infection periods is critical when working with protectant biologicals.

In this episode, you will hear:

• Why more new products in the pipeline are biologicals rather than conventional chemistries

• How Cornell's high‑pressure pathology vineyard reveals the real-world limits and strengths of biologicals

• Why many biologicals are strictly protectants and must be applied before significant disease is present

• How tank mixing biologicals with conventionals can reduce cost-effectiveness without improving control

• Why understanding water chemistry, pH, and product formulation is now an essential spray-program strategy

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 at https://www.virtualviticultureacademy.com! Save $75 off your first year of membership with the code Underground at checkout.

Episode Sponsor:

Today's episode was brought to you by Shellt Grow Tubes and Vigneron Toy Store

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 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.

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.

Small vineyard decisions made early in the season can create major ripple effects later in the year, and in this episode, Fritz breaks down three vineyard management tasks that are frequently skipped, delayed, or underestimated despite their outsized impact on vine health, fruit quality, and long-term vineyard performance.

Fritz focuses first on shoot thinning and explains why timing is everything. He walks through the economic and practical advantages of thinning early, including improved spray penetration, better airflow, easier hand harvesting, and even reduced pruning labor during dormancy.

He then explains why bloom and veraison sampling windows are critical for understanding nutrient status and preventing deficiencies before they become costly problems. Lastly, he tackles water stress monitoring and the common misconceptions surrounding vineyard stress.

Listen in for practical ways growers can monitor irrigation effectiveness, evaluate soil moisture, and avoid relying solely on visual assumptions about vine stress levels. Remember, better data leads to better vineyard decisions.

In this episode, you will hear:

• Early shoot thinning can improve fruit quality, airflow, spray coverage, and long-term pruning efficiency

• Delayed shoot thinning increases labor costs and creates more winter pruning wounds susceptible to trunk disease

• Tissue sampling at bloom and veraison helps growers identify nutrient deficiencies before productivity suffers

• Leaf blade sampling may provide more reliable nutrient data than petiole sampling for many nutrients

• Water stress should be monitored with both field observation and measurable soil moisture data

• Excess vigor, nutrient imbalance, weather extremes, fungal disease, and insects can all contribute to flower browning during bloom

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:

Get Fritz's Shoot Thinning, Tissue Sampling, and Plant Stress resources available for podcast listeners at VirtualViticulureAcademy.com/tasks.

Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button.

Episode Sponsor:

Today's episode was brought to you by SensorInsight and Clemens Technologies.

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 change over a given season. Visit them today at https://sensorinsight.io. And don't forget to mention the code Underground to receive a discount on your SensorInsight solution.

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 thomas@clemens-america.com with any questions.

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.

We are back with another solo episode! Fritz dives into the world of Reddit viticulture advice to separate helpful guidance from misleading recommendations. Using real vineyard and winemaking questions pulled from Reddit threads, Fritz evaluates the quality of the responses while adding his own professional perspective.

The episode covers a wide range of vineyard topics, but throughout it, Fritz highlights an important lesson for growers at every level: context matters. Many online answers contain kernels of truth, but successful vineyard management depends on site conditions, climate, soil, vine age, regional disease pressure, and long-term goals. He explains why broad internet advice often lacks the specificity growers actually need to make confident decisions.

Listeners will come away with a fresh perspective on vineyard establishment, irrigation management, pruning strategies, disease prevention, and realistic expectations for small-scale winegrowing projects.

In this episode, you will hear:

• Establishing vineyards in cool climates like the UK and Northern Europe

• PIWI grape varieties and disease-resistant planting strategies

• Realistic timelines for vineyard establishment and first harvests

• Challenges of starting and managing a small hobby vineyard

• Irrigation management for young vines during extreme summer heat

• Reviving neglected Frontenac and Edelweiss vineyards in the Midwest

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:

If you're starting a vineyard or thinking about starting a vineyard, visit https://www.virtualviticultureacademy.com/growsmart to get Fritz's online Prospective Winegrape Grower Course to help you get your vineyard planned and planted correctly from the start. Use the code PODCAST at checkout to save $89.99 as a thank you for being a podcast listener.

Get more information from Fritz about soil moisture sensors – types of sensors, location and placement, installation, and understanding soil monitoring data at https://www.virtualviticultureacademy.com/sensor.

Have a vineyard question? Go to VineyardUndergroundPodcast.com and click the Ask Fritz button.

Episode Sponsor:

Today's episode was brought to you by Vintner's Vault and Vigneron Toy Store.

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 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.

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.