Even more important than their use in juices and jams, this species has been used as root stock for less hardy grape varieties. Crossings of the riverbank grape with the true grape (V. vinifera) and other wild grapes has produced varieties which can be grown under conditions where the true grapes don’t thrive. In Finland, for example, the varieties ‘Beta’ and ‘Valiant’ can be grown successfully. They are hybrids of riverbank and fox grape (V. labrusca). However, even these varieties only produce ripe fruits out of doors in the warmest spots, and perhaps not every year; in the protection of even an unheated greenhouse crops are more reliable.
At Mustila there are riverbank grapes of very northern natural provenances, which are hardier than the varieties. Although the forest-like conditions at the Arboretum are perhaps not the ideal setting, some varieties have also been planted against warm walls in the hope of fruiting.