2019 ASHS Annual Conference

Evaluating Vitis vinifera Productivity In Sheridan, Wyoming
Heidi Schueler and Alisha Bretzman with Ami Erickson

Agriculture Department
Sheridan College - Northern Wyoming Community College District and
University of Wyoming - Sheridan Research and Extension Center

Poster

In the summer of 2014, 350 Vitis vinifera (grapevines) originating from the USDA cold-hardy grapevine germplasm repository in Geneva, NY were planted in Sheridan, Wyoming at the Sheridan Research and Extension Center. Thirty-five different cultivars were planted and evaluated for winter survival and bud break. Based on 2015 data survival rate was 73% and average bud break began on May 14th- June 9th. Certain cold hardy varieties had a 100% survival rate, including: ‘Marechal Foch’ and ‘Osceola Muscat’ and ‘Frontenac’ (Dhekney et al. 2015).
Grape production has many challenges in Wyoming, including: deep winter freezes and mid-winter thaws; early spring frosts; early fall frosts; a dry, windy climate; and poor ground water quality. Despite these challenges, many of the original 350 vines that were planted have survived and have begun to produce. However, little data is currently available.
Our goal for the 2019 growing season is to identify which of the 35 cultivars holds a profitable yield potential for grape production in Wyoming. We will base our evaluation on factors including growing degree-days (GDD) on bud break and grape harvest, weight and size of grape clusters, grape sugar concentration, and overall health of the vines. Growing degree-days typically begin in late March to early April and end in October. Growing degree-days are expressed as temperatures above 50° F, when bud break and cell division can take place. From observations of fall 2018 harvests, we expect to see potential profitable yield from ‘Frotenac’, Frontenac Gris’ and ‘Osceola Muscat.’