Thompson Seedless, also known as Sultanina, is the most widely planted white seedless grape in the world and the backbone of the California table-grape and raisin industries. It traces to an ancient seedless cultivar from the Ottoman and Persian regions and was popularized in California in the 1870s by William Thompson. The vigorous vine produces long, large clusters of small oval, pale green to amber berries. Because natural berries are small, commercial growers girdle canes and apply gibberellic acid to increase size. It is the source of most golden and natural raisins and is also pressed for grape juice and neutral wine. In the home vineyard it needs a long, hot growing season and cane pruning to fruit well.
Flavor Profile
Sweet and mild with a light, crisp, sugary flavor and no seeds; low acidity makes it a classic dessert and raisin grape.
Visual Characteristics
Long, well-filled cylindrical clusters of small oval berries that ripen from green to translucent pale amber.
Growing Tips
Requires a long hot summer and cane (not spur) pruning; girdling and gibberellic acid are used commercially to enlarge the berries.
Where to Buy
Sourcing information coming soon. Check local nurseries and seed banks for availability.