The study was carried out on a mature selection of seabuckthorn subsp. fluviatilis grown in Rome, Italy. Female flower bud differentiation is a long process that takes several months to be accomplished; it starts at the beginning of summer, goes on through winter and is completed during bud swelling before anthesis (mid march).

The periodical sampling of the buds showed that until mid June only the leaf primordia are visible in the bud complex, while at the beginning of August flower organogenesis has already taken place and flower primordia are well visible. During summer until the end of the growing season new flowers differentiate, starting from the bud base to the tip, so that within the same bud complex, many flowers at different development stages can be seen. Before plant rest the flower structure is completed, but during winter time the flower buds continue to increase their volume until anthesis.