Pruning Sultana vines by the arched cane system

Abstract

Pruning Sultana vines in the Murray Valley by the system of 'arched canes' is described. In two experiments there were trends towards slight increases in crop despite smaller bunch weight when the canes were arched downwards instead of wrapped tightly around thetrellis wire. Downward arching did not greatly affect overall vine performance, but it modified the distribution of growth and yield along the canes, leading to more bunches on the middle part of the cane and shorter shoots on the distal part of the cane. Arching the canes upwards gave similar results to wrapping and showed no commercial promise. Harvest pruning was somewhat faster when the canes were arched downwards, but there was no quality difference in the trellis dried fruit. Winter pruning was speeded up by up to one-half of normal pruning time when the canes were arched, particularly when clips were used to attach them to the trellis wire. Vines pruned by arching had sufficient replacement canes although they produced fewer mature shoots near their crowns than vines pruned by wrapping. It is concluded that pruning Sultana vines by arching canes downwards leads to several beneficial changes, i.e. reduced bunch weight without loss of crop, less fruit clumping where the canes of two adjacent vines meet, shorter terminal shoots, and reduced pruning time. This can be achieved without major changes of the trellis.