2025 Post-Veraison in Pennsylvania - September 2

Report #1: samples taken week of August 25, 2025

This is the first weekly report for the third season of Post-Veraison in Pennsylvania (PVIP), a grape maturation reporting system across Pennsylvania vineyards. Reports will consist of weekly grape ripening updates from cultivars that are planted widely across Pennsylvania (PA) vineyards (as based on feedback documented within Cultivars in the Commonwealth). Henceforth, PVIP reports will review the ripening patterns of some, or all, of the following cultivars: Cabernet franc, Chambourcin, Chardonnay, Riesling, and Vidal blanc. Due to the time required for grape samples to be shipped, processed, and measured, weekly reports will reflect maturation from the previous week. Participating stakeholders for the 2025 edition of PVIP manage vineyards in the following Pennsylvania counties: Chester, Erie, Fayette, Lehigh, and Snyder; thanks to these stakeholders for their participation and collaboration on this project. If you have a commercial vineyard in Pennsylvania, please let us know if you are interested in participating in a future edition of PVIP.

Note – Compared to fruit with lower soluble sugars (Brix) and pH and higher titratable acidity (TA), fruit with higher Brix and pH and lower TA is generally indicative of more advanced maturity. Of the counties from which fruit composition was measured for this report, Cabernet franc was most mature in Fayette (southwestern PA near West Virginia border) and least mature in Erie County (northwestern PA near New York/Ohio border) (Table 1). Cabernet franc fruit maturity was similar between the Chester and Snyder County vineyards. Chambourcin, a later ripening, red-berried hybrid cultivar, had lower pH and higher TA than Cabernet franc grown in the same vineyards. While there was variation in fruit chemistry between locations, Chambourcin maturity was similar across the Chester, Fayette, and Snyder vineyards, with the greatest Brix measured in Snyder, the highest pH in Chester, and the lowest TA in Fayette. Chambourcin was least mature in Erie. Riesling Brix was similar between the two vineyards in Chester and Fayette County, while TA and pH were lower in Fayette compared to Chester County. As observed with the other cultivars, Riesling was least mature in Erie. As documented by lower Brix and higher TA, Vidal blanc was less mature in Erie compared to Snyder County.

Pennsylvania stakeholders have already reported harvest for some cultivars in the 2025 vintage, including Chancellor, Chardonnay, Pinot noir, and Seyval blanc. In some cases, cultivars were picked at relatively low Brix and pH and high acidity to produce sparkling or rose wines. If you have harvest updates you wish to be included in this report, please email them to viticulture@psu.edu.

The data in this report is possible due to the funding and support of the Pennsylvania Wine Marketing and Research Program. The authors and collaborators are grateful for the support.