Sustainable Thermaculture® technology improves wine, and bottom line, in challenging East Coast climate.

Barrel Oak Winery in Northern Virginia faces constant growing challenges presented by typical East Coast weather: Rain, freezing temperatures, and humidity. “With our inability to produce organic wine in this state, we started looking for solutions to help us get one step closer,” reported Barrel Oak’s Winemaker and Viticulturist, Shai Van Gelder.

Van Gelder approached Agrothermal Systems® looking to increase overall yield, improve wine quality, and explore Integrated Pest Management (IPM) potential while maintaining a sustainable approach. The trial was conducted during the 2017 season on 24 rows of premium Petit Manseng and 17 rows of premium Petit Verdot following standard Thermaculture protocols. Thermaculture applications were additionally distributed throughout the vineyard whenever time permitted.

Pest and Mildew Control

In general, the test grapes experienced less insect damage. During the season, a mite infestation occurred in non-trial blocks. Heat-treatments eradicated the entire population. “Not a single mite could be found,” Van Gelder recalled, “one application eliminated the need for miticide and saved Barrel Oak over $700 in material cost alone.”

According to Agrothermal CEO Marty Fischer, "Small, soft-bodied insects and any insect that goes through nymph or larval life cycle stages on agricultural crops are susceptible to the level of heat our equipment delivers. We have seen consistent success controlling mites, thrips, aphids, and early stage leaf hoppers.”

While the trial did not involve fungicide testing specifically, Van Gelder successfully treated and suppressed powdery mildew whenever he saw a buildup. This confirmed other recent work done in California with Dr. Doug Gubler and several other growers who have experienced good powdery mildew control with Thermaculture.

After witnessing Thermacultures’ effect on powdery mildew and mites, Van Gelder sees great potential to treat for other pests plaguing Virginia winegrowers, “I plan to start experimenting with, and developing protocols for spotted wing drosophila, climbing cut worm, and downy mildew.”

Increased Yield

At time of harvest, Barrel Oak experienced an amazing 30% increase in Petit Verdot. “I am incredibly happy,” stated Van Gelder, “The yield increase shows that the technology does what it says it does.”

Fischer remarked, “Our customers see an average yield increase of 16%. This can be significantly higher when foul weather occurs during bloom that inhibits climatic conditions for good fruit set. We can simulate good, hot, dry conditions when Mother Nature gives the grower wet and cool weather.”

When asked about the return on investment, Van Gelder stated, “I believe that by using this technology, we can decrease our dependency on conventional chemicals, and improve our ability to increase production of our own estate fruit.  This leads us to rely less on outside fruit contracts, and focus on the Terroir of Barrel Oak.” Between the savings on pesticides and the greater yields, Thermaculture will ultimately improve the bottom line at Barrel Oak.

Improved Wine Quality

Van Gelder and his peers experienced significant sensory differences in both varieties.  “The winemakers and industry professionals all tended to like the treated Petit Manseng as it adds an element we aren’t used to. It is a lot more acid-driven, has good minerality, and has a great finish that lingers. There’s fruit but it’s more mango and grapefruit.” Van Gelder realized, “I can use this to improve regular Petit Manseng. It will provide an extra instrument in the orchestra that will hit the right note every time and create a more harmonious, more complex wine.”

As for the Petit Verdot, “The treated wine had a more interesting and complex tannin structure that will, over time, round out and soften to create a more elegant wine. It will age well.”  Van Gelder continued, “I appreciate the fact that it was delicious even with the 30% increase in yield. It shows that the quality of berries is keeping up with the quantity.”

Master of Wine, Philip Goodband agrees with Van Gelders assessment, saying, “By comparison, the control Petit Verdot seemed to have a more aged colour and whilst very good and certainly an excellent example of the varietal, seemed to lack the fruit definition of the treated wine, and was almost ready to drink.”


Barrel Oak Winery and Shai Van Gelder are thrilled with the overall trial results.

“It’s a win-win. Barrel Oak benefits from the results of the technology, and I get to do the research and develop the protocols. If there is anything I can do to make farming better in Virginia, I’m on board. If it helps another farmer grow a better grape, then it helps Virginia’s wine industry grow.”

Fischer concluded, "We expected great results would occur for East Coast growers, and that has now been proven thanks to Barrel Oak Winery, which we are pleased to have as our East Coast development partner. They pioneered technology protocols to meet local needs. Next season we will work with Shai and our Science Advisers to address other regional challenges such as downey mildew and spotted wing drosophila."

Agrothermal Systems is based in Napa, California and is a DBA of Lazo TPC Global, Inc. a California Corporation. Agrothermal Systems has pioneered the use of Thermaculture treatment services as a sustainable, low cost technology to reduce fungicide and insecticide needs, increase yields, and improve wine quality. The company holds patents on Thermal Pest Control and has patents pending on other aspects of the technology.

Related Articles

Get Started Today

Learn how Agrothermal Systems can help your business experience the benefits of Thermaculture

8 + 7 =

Pin It on Pinterest

Share This