Grapes ripening on the vine in MSU's vineyard

MSU's experimental vineyard, located at the MSU Horticulture Farm west of Bozeman, was established to trial cold-hardy grape varieties. It was planted in 2010 with canes from the USDA grape germplasm collection in Geneva, New York, and contains 19 varieties of cold-hardy grapes. All vines are on their own rootstock.  

Grape Varieties

The grape varieties included in the MSU vineyard are listed below, along with information on berry color and the typical use for each variety. USDA hardiness ratings are based on the average minimum temperature that the plant can withstand. The Bozeman area is rated Zone 4, which means that the average annual minimum winter temperature is -20 to -25 degrees Fahrenheit. Lower hardiness ratings mean that plants are more cold-hardy. For more information on plant hardiness, visit the USDA's hardiness zone website.  

Variety

Berry Color

Use

USDA Hardiness

Beta Black Juice 3
Kay Gray White Table 3
St. Croix Red Wine 3
Valiant Black Juice 3
Bluebell Black Juice 3
Elvira White Wine 3
Worden Black Table 4
Concord Black Juice 4
Edelweiss White Wine 4
Maréchal Foch Black Wine 4
Fredonia Black Juice 4
St. Pepin White Wine 4
Swenson Red Red Table 4
Van Buren Black Table 4
Aurore White Wine 5
De Chaunac Black Wine 5
Seyval Blanc White Wine 5
Vignoles White Wine 5
Vanessa Red Table 5

Further varietal information

Observations

There are currently no active research projects in the vineyard, but vines are being maintained and some general information from the past four growing seasons is listed below. Data points tracked include leaf break on vines, bloom date, veraison (when the grapes start to ripen), harvest date and yields, and Brix content of berries at harvest. Brix content, measured in degrees Brix (°Bx), is the measure of sugar content in berry juice. 

MSU's Western Agricultural Research Center, located in Corvallis, has also done extensive research on cold-hardy grapes in western Montana. Many of the varieties found at the Horticulture Farm are also included in WARC's study. For more information and research results, check out their research on grapes in Montana.

2018 Season

Variety

Bud Break

Bloom

Fruit Set

Veraison

Harvest Date

 Yield (kg)

Brix Content (°Bx)

Beta May 22 June 28 July 6 August 30 September 25 2.6  20
Kay Gray May 29 June 30 July 6 August 30 September 25 0.75  19
St. Croix May 29 July 3 July 13 August 30 September 25 2.4  17
Valiant May 22 June 22 July 3 August 13 September 25 7.15  20
Bluebell May 29 June 28 July 6 August 30 September 25 5.45  17
Elvira May 22 June 28 July 9 September 7 September 25 0.75  13
Maréchal Foch May 22 July 3 July 13 August 22 September 25 2.75  20
St. Pepin May 29 July 6 July 13 August 22 September 25 1.75  19
Swenson Red May 29 July 6 July 13 August 30 September 25 0.15 18
Van Buren May 29 July 18 July 25 September 7 September 25 0.1  13
Aurore May 22 July 6 July 13 August 22 September 22 0.1  19
Seyval Blanc May 29 July 20 July 25 September 7 September 25 0.1  12

*A hard freeze on the night of June 11 killed most of the new growth on the vines and greatly affected production over the 2018 season. The arrival of freezing fall temperatures also dictated the harvest (September 25) of grapes, even though not all varieties had reached desired Brix levels. Only varieties with grapes ripe enough to harvest are listed in the table above; multiple varieties did not recover in time to produce edible berries, and unripe clusters were not harvested or included in the data. 

2019 Season

Variety

Bud Break

Bloom

Fruit Set

Veraison

Harvest Date

Yield (kg)

Brix Content (°Bx)

Beta June 1 July 5 July 9 September 5 September 27 3.8  16
St. Croix June 3 July 9 July 16 September 16 September 27 1.7  12.5
Valiant June 1 July 5 July 8 August 20 September 27 17.7 17
Bluebell June 2 July 9 July 16 September 11 September 27 2.2  13
Maréchal Foch June 2 July 9 July 16 September 5 September 27 4.3  16.5
St. Pepin June 5 July 9 July 16 September 5 September 27 2.3 15.5

*As in 2018, cold spring weather and a cool summer greatly affected the grape vines and reduced crop yield on all varieties except Valiant, and the arrival of freezing fall temperatures dictated the harvest of grapes on September 27. Only varieties ripe enough to eat (°Bx>12) were harvested, and unripe grape clusters were not harvested either.

2020 Season

Variety

Bud Break

Bloom

Fruit Set

Veraison

Harvest Date

Yield (kg)

Brix Content (°Bx)

Beta May 27 June 27 July 2 August 18 October 9 1.8 22
Kay Gray May 29 June 27 July 6 August 26 October 9 0.04 19.5
St. Croix June 3 July 6 July 13 September 3 October 9 0.3 18.5
Valiant May 27 June 24 June 30 August 14 October 9 9.0 19.5
Bluebell June 3 July 6 July 13 September 7 October 9 0.1 17.5
Maréchal Foch May 29 June 29 July 8 August 20 October 9 1.3 20.5
St. Pepin June 3 July 6 July 13 August 24 October 9 0.6 21.5

*Early freezing temperatures in October 2019 damaged or killed many of the vines, resulting in a somewhat slow start to the 2020 season and reduced yield on most varieties (Valiant seems to have been the exception). However, warm fall temperatures allowed for a later harvest than in past years and resulted in improved Brix content at harvest. 

2021 Season

Variety

Bud Break

Bloom

Fruit Set

Veraison

Harvest Date

Yield (kg)

Brix Content (°Bx)

Beta June 2 June 22 June 28 August 27 September 28 0.4 24
Valiant May 30 June 20 June 25 August 5 September 28 5.8 21.5
Maréchal Foch June 10 June 28 July 9 September 10 September 28 0.06 12

*Abrupt freezing temperatures in October 2020 and unpredictable weather over the winter resulted in high vine mortality. Valiant was the only variety with a 100% survival rate, and surviving vines produced fewer grapes than in previous years. However, hot weather over the summer sped up development and resulted in higher Brix contents at harvest than years with similar harvest dates. 

 

The Horticulture Farm vineyard has a large enough footprint that it is not practical to cover the vines in response to cold temperatures. However, home growers with a limited number of vines could potentially cover their vines at night in spring to protect against late frost damage, and again in fall to extend the season and further ripen grapes. Another option if only light frost is expected (in spring or fall) is to run sprinklers on the grape vines overnight. This will coat leaves and shoots with a thin layer of ice and insulate them against frost damage. (This technique was used successfully several times during the 2020 growing season.) 

Variety Recommendations

Based on several years of observations, the following grape varieties appear to be the most cold-hardy and productive in the Gallatin Valley:

  • Beta - tolerates some cold damage and ripens quickly
  • Valiant - the best producer overall and very cold-hardy; ripens about the same time as Beta
  • Bluebell - the best-tasting grape, but doesn't ripen as quickly as Beta or Valiant and isn't quite as cold-tolerant
  • Maréchal Foch - ripens quickly, but doesn't produce quite as much as Valiant