Black Diamond, also known as Cannonball or Florida Giant in some regions, is a classic large round heirloom watermelon that was widely grown in the mid-20th century before hybrids dominated the market. It is famous for producing enormous, heavy fruit with a very dark blue-green rind and sweet, deep red flesh. Black Diamond is an open-pollinated variety cherished by home gardeners for old-fashioned flavor and for growing show-sized melons. The thick rind stores and ships reasonably well. Because of its large size and long season requirement, it is best suited to gardens with plenty of room and a warm, extended growing period.
Flavor Profile
Sweet and juicy with classic old-fashioned watermelon flavor and deep red flesh.
Visual Characteristics
Very large round fruit weighing 30-50 pounds with a dark blue-green rind and bright red flesh.
Growing Tips
Requires a long, warm season and abundant space; thin to fewer fruit per vine to maximize size.
Resistance Information
Disease Resistance
Moderate field tolerance
Where to Buy
Sourcing information coming soon. Check local nurseries and seed banks for availability.