One of the first modern grape varieties released by the University of Minnesota along with Elmer Swenson was Edelweiss in 1977, although its breeding history dates to the 1950s. This grape fits into several categories as it can be used for wine making but also enjoyed as a table grape or for fresh juice. It has large clusters of white-seeded grapes with a Concord-like flavor. May need winter protection. The berries are big, luscious, and aromatic.
Fruit characteristics
Edelweiss produces berries that are light yellow in color. They are large (3.13 g) and on clusters around 127 g. Yield per vine is about 11 lbs.
Hardiness
This variety can survive to low temperatures, but is not as hardy as Frontenac or Itasca.
Vigor
This variety can be very vigorous with limited winter injury.
Bud break and harvest timing
Compared to other varieties, Edelweiss has an early bud break which can put it at risk for late frost events. Harvest is typically late August in Minnesota, which puts it earlier than most of the other commercial varieties.
Harvest parameters
Monitoring of juice chemistry is important for all grape varieties, but taste is equally important. Edelweiss, much like Brianna, can become “over ripe” in its flavor and aroma profile and thus a target soluble solids content of 14-17 °Brix is suggested. The pH may be a more reliable tool for picking Edelweiss, usually below 3.3 is preferred.
Training systems
Due to its procumbent growth habit, Edelweiss is well suited for training to a Single High Wire trellis system. The vigor of this vine could make it suitable for split canopy systems like a Geneva Double Curtain training system. This variety does not do well on high pH soils. Edelweiss is a great option for the homeowner and backyard grape grower because of the different uses for the fruit as well as its tolerance to pests. The vines can be trained over an arbor or on a sturdy fence.
Pest susceptibility
Edelweiss is reported as moderately susceptible to anthracnose, botrytis bunch rot, and powdery mildew. It is slightly susceptible to downy mildew, black rot, and crown gall. Considerations for the homeowner include the use of 2,4-D (and Dicamba) in lawns, as this variety, like many grapes, is highly sensitive. Unlike other V. labrusca based hybrids, Edelweiss is not sensitive to injury from sulfur and copper applications.