Shipping stress causes a variety of quality problems with potted flowering plants. In the highly ethylene-sensitive species Pelargonium xdomesticum, shipping results in flower petal abscission and unsatisfactory quality for the receiver. The extent of accidental pollination during shipping and its role in petal abscission was investigated for four cultivars of Pelargonium xdomesticum. Petals were increasingly likely to abscise during shipping as flowers matured, but cultivars varied in the extent of petal abscission at each stage of development. Petal abscission after intentional pollination varied among cultivars and was highest for freshly opened flowers, but never exceeded 25%. Accidental pollination during simulated shipping occurred to a greater extent in those cultivars with a small distance between the stigma and anthers, but this accidental pollination was unrelated to shipping-induced petal abscission. Therefore stage of floral development and cultivar are the most important factors affecting shipping-induced petal abscission.