From late summer into fall, Southerners start looking for muscadines — a popular grape native to the Southeastern U.S. Selections run from the dark purple, thick-skinned traditional muscadine to a light golden-green variety. Soon, growers and consumers can add a new red variety to the mix.
The University of Georgia College of Agricultural and Environmental Sciences’ muscadine grape team, led by horticulture Professor Patrick J. Conner, developed a variety of muscadine for those who prefer the sweet taste of a berry with limited muscadine flavor.
“The unusual red color of this berry really makes it stand out,” Conner said. “But the tender skin and crisp flesh of this variety are what truly make it unique. The texture of this variety is a marked change from traditional muscadines, which are often known for having tough skins and a soft pulp.”
Researchers found ‘RubyCrisp’ to be a good fit for pick-your-own operations and home gardens because of its distinctive taste and texture and excellent productivity. Unfortunately, commercial production is not a good fit for this specialized berry, because it often cracks with rough handling. However, ‘RubyCrisp’ vines can flourish in the backyards of at-home cultivators looking to try the newest muscadine.
‘RubyCrisp’ originated in Tifton, Georgia, as a result of a cross between ‘Supreme’ and ‘Tara’ varieties. ‘Supreme’ produces black berries with exceptional size and firmness. ‘Tara’ produces bronze berries with dry pedicel scars that ripen early in the muscadine harvest season. In 2011 the ‘RubyCrisp’ vine was chosen because of its large berry size, flower type and outstanding flavor.
The original ‘RubyCrisp’ vines were tested on UGA experiment plots in Tifton and at a commercial vineyard in Wray, Georgia. There, researchers discovered that given the large berry size and high production potential of ‘RubyCrisp’, growers may need to limit vine fruitfulness by increasing the distance between fruiting spurs or thinning the crop so that the vine is not weakened by maturing excessive crops.
UGA researchers also found that heavy rainfall can lead to fruit cracking. ‘RubyCrisp’ has a mid-season harvest date around Aug. 21 in south Georgia and has perfect flowers so it does not need a pollinator.
“Because further study is needed to explore the optimum environment for producing this vine, especially its cold hardiness, we suggest growers in northern muscadine regions refrain from planting large numbers of ‘RubyCrisp’ until more data is collected,” Conner said.
UGA has the oldest muscadine breeding program in the U.S. The program began in 1909, and since then, it has released over 30 cultivars and counting. The program focuses on continued improvement of the muscadine grape by developing new cultivars that satisfy the needs of growers and the demands on consumers. The UGA muscadine breeding program works to create new cultivars that combine large berry size with perfect flowers, expand the harvest season with earlier and later ripening dates, and produce berries with dry stem scars, crisp flesh and tender skins.
A list of nurseries licensed to propagate ‘RubyCrisp’ muscadine is available by contacting Conner at firstname.lastname@example.org. For more information about the UGA muscadine grape breeding program, visit muscadines.caes.uga.edu.