Muscadines
A Southern Tradition
Muscadine grapes (Vitis rotundifolia) are one of the South’s sweetest natural treasures—famous for their rich, “candy-like” flavor and incredible ability to thrive in heat and humidity. Native from coastal Virginia through Florida and west to eastern Texas, muscadines flourish where summer is intense and winters stay above 10° F.
While familiar wine and table grapes belong to the 38-chromosome Vitis subgenus, muscadines belong to the 40-chromosome Muscadinia subgenus. That genetic divide makes crossbreeding nearly impossible, so muscadines have followed their own independent path of improvement for more than a century.
Muscadines are beloved for their natural strengths: outstanding disease resistance, remarkable insect tolerance, and unmatched adaptation to the southern climate.
Wild muscadine vines have small black berries (left) produced on vigorous vines (right) that can extend into the tops of the forest canopy.
But they also come with quirks including small clusters, uneven ripening, and berries that separate from the stem when ripe. Their thick skins, large seeds, and soft pulp have challenged breeders for generations
Hybrids between V. vinifera and V. rotundifolia such as the vine above can have excellent vigor but are usually sterile and a breeding dead-end.
Comparison of the size of muscadine (left), vinifera (center) and labrusca (right) grape bunches.
A Century of Innovation at the University of Georgia
1909: The Beginning
The UGA muscadine breeding program began in 1909 at the Griffin Experiment Station.
Early pioneers H.P. Stuckey and J.G. Woodroof used wild selections and early cultivars to breed muscadines with sweeter flavor and berries that held firmly to the vine. Their thirteen releases transformed muscadines into a favorite backyard fruit throughout the South, just in time for WWII to pause the program.
Many older southerners have pleasant memories of sitting in the cool shade of an overhead muscadine arbor and enjoying the sweet fruit.
1951–1968: The Second Era
The second era of the program, led by B.O. Fry from 1951–1968, propelled muscadines into true commercial relevance. Fry focused on transforming the fruit with larger berries, rich bronze color, and elevated sugar content.
His 1955 release ‘Higgins’ introduced nearly 9-gram berries, an astonishing leap forward. Even more importantly, it reliably passed that size advantage to its offspring. Building on this momentum, Higgins became the cornerstone parent of a new generation of standout cultivars, including Jumbo, Cowart, and the iconic Fry which remains a fresh-market standard to this day.
These advances didn’t just improve fruit quality; they ushered muscadines out of backyard gardens and into grocery stores, establishing the crop’s modern commercial footprint.
The release of superior fresh-market muscadine cultivars from UGA led to the establishment of commercial muscadine vineyards like Paulk Vineyards shown above, the world’s largest muscadine vineyard located in Irwin Co. Georgia.
1970: Fry is Released
The release of Fry in 1970 marked a turning point in muscadine history. Named for its creator, this cultivar delivered the full package of traits needed for a true commercial fresh-fruit muscadine. Most importantly, it was big, beautiful, and delicious.
Weighing nearly 13 grams, a size unimaginable before its introduction, its impressive berry size not only created outstanding eye appeal but also reduced harvest labor by filling baskets faster. Equally valuable was its ability to taste sweet even before full ripeness, allowing growers to harvest while the fruit was still firm enough for excellent shelf life. Together, these attributes made Fry the cornerstone of Georgia’s rapidly expanding fresh-fruit muscadine industry in the 1970s and 1980s.
Just as remarkable, it proved to be an exceptional parent, appearing in the pedigree of nearly every major fresh-market muscadine released since, a legacy that still shapes the industry today.
The Fry cultivar, released in 1970.
1969–1996: Lane Ushers in the Modern Era
From 1969–1996, breeder R.P. Lane ushered in the modern era by combining large fruit with “perfect flowers”, self-fertile blossoms that produce both pollen and fruit. Traditional muscadines required male pollinizer rows that produced no crop.
Perfect-flowered cultivars allowed every vine to produce fruit, dramatically boosting yield. Lane’s standout releases, including ‘Triumph’ and ‘Tara’, proved that large size and perfect flowers could coexist.
Female (pistillate, left), hermaphroditic (perfect; center), and male (staminate, right) muscadine flowers.
‘Triumph’ (left) and ‘Tara’ (right) muscadines combined the quality and size of ‘Fry’ fruit with perfect flowers that require no pollinizer to produce a crop.
Today's Wave of Improvements
Since 2004, the program has been led by Dr. Patrick Conner, whose work focuses on developing perfect-flowered cultivars with very large berries, allowing growers to switch entirely from less-productive female vines to high-yielding self-fertile varieties. Dr. Conner is also redefining muscadine texture by breeding for crisp skins and firm, juicy flesh, allowing fully ripe grapes to meet fresh-market quality standards.
His breakthrough varieties include Paulk™, the first perfect-flowered muscadine with exceptionally large berries (15–16 g), RubyCrisp™, a crisp-textured, thin-skinned, ruby-red muscadine unlike anything on the market, and the latest, Gold Delight™, a beautiful bronze cultivar with excellent disease resistance.
Paulk™ (left), RubyCrisp™ (center), and Gold Delight™ are the first muscadine cultivars to fulfill the grower demand for very large berry size (15-16 g) combined with perfect flowers.
Pink stars in the map indicate the source location of new diverse germplasm introduced into the UGA muscadine breeding program from throughout the native range. Original founding selections are shown in black font.
Dr. Conner is also working to broaden the genetic foundation of muscadine breeding, addressing a long-standing limitation in the crop’s history.
For more than a century, fewer than a dozen founding selections, most originating from the coastal areas of the Carolinas, have shaped every major muscadine cultivar. This repeated use of the same parents has gradually increased inbreeding and reduced vigor in many modern releases. To reverse this trend, the breeding program at University of Georgia is actively collecting wild muscadine germplasm from across the species’ native range.
By infusing this new diversity into the breeding pipeline, the program aims to restore vigor, expand genetic potential, and power the next generation of superior muscadine cultivars.
The Future: Uniting Two Worlds of Grapes
In 2024, UGA joined grape researchers across the United States in a major USDA NIFA project: “Through the Grapevine: Developing Vitis × Muscadinia Wide Hybrids for Enhanced Disease Resistance and Quality” (SCRI Award #2024-51181-43236).
This national effort aims to unlock the genetic secrets of both grape groups and build new “bridge hybrids” that allow muscadines and traditional grapes to share desirable traits. The goal is bold: improve both industries while bringing the flavor of muscadines to grape lovers nationwide.
The grape scientists and industry professionals working together on the “Through the Grapevine” project.