Honey bees, Apis mellifera, are widely used to pollinate orchards of selfincompatible trees. But the pollination effectiveness of foragers can be limited by a lack of compatible pollen or its uneven availability throughout an orchard, and pollen dispensers placed at the hive entrance have then been recommended to improve pollination. Yet very few field studies have assessed the usefulness of these devices and so we conducted such a study with Bee Booster™ pollen dispensers over 2 years in 2 isolated commercial apricot orchards planted solely with the early selfincompatible Prunus armeniaca ‘Robada’. Over 2000 flowers on control clusters were isolated under pollenproof bags while a similar number of treated flowers were left exposed to bee visits on a mild and sunny day when the dispensers were fitted on the hives and supplied with the recommended amount of compatible pollen (‘Tomcot’). Flowers hand-pollinated with this pollen served as positive controls while flowers hand-pollinated with self-pollen served as negative controls. In all experiments, hand-pollination with dispenser pollen gave increased fruitlet and fruit set, but dispensers placed on the hives did not (P ≥ 0.32). A test conducted with 3 ‘Orangered’ trees caged individually under anti-hail nets with a small honey bee colony gave similar results as fruit set was similar in the control cage and in the cage with the hive fitted with a pollen dispenser. Honey bees leaving the dispenser-fitted hive did wade through the pollen, but they readily started packing the pollen clinging to their body into their corbiculae. The pollen in the dispensers was thus quickly removed, but little, if any, reached the apricot stigmas. Our results suggest that the effectiveness of pollen dispensers should be carefully assessed under field conditions and for each crop prior to being recommended to improve pollination.