Fruit Firmness and Holding Ability in Highbush Blueberry—Implications for Mechanical Harvesting

Fruit firmness plays a critical role in the ability of blueberry cultivars to be machine harvested. We recently completed a survey of “initial” fruit firmness in a large group of highbush cultivars and southern highbush cultivars with varying percentages of V. corymbosum L., V. angustifolium Ait., V. ashei Reade, V. darrowi Camp ancestry. The cultivars exhibited an approximately 2.4-fold difference between the softest and the firmest selections. Many of the firmest selections were newer cultivars with some V. darrowi ancestry. Cultivars also differ in their ability to retain quality once ripeness has been achieved. In preliminary studies, ‘Legacy’ appeared best at retaining firmness, but several other cultivars retain good quality by merit of having very high initial firmness values. The ability to retain quality presents growers with more harvest options, in that, it might allow greater percentages of ripe fruit to accumulate before harvesting, thereby minimizing harvest expenses. Initial studies, however, indicate that utilizing holding ability under field conditions may be a double-edged sword. There are tradeoffs between harvest frequency and yield.