Abstract: Chaste tree (Vitex agnus castus L.) is one of the most important native shrubs in arid and semi arid Mediterranean and western Asia regions, widely used from ancient years for medicinal and other purposes. Laboratory and greenhouse experiments were conducted in Greece, in order to investigate the germination behavior of untreated seeds and seeds subjected to several pretreatments and subsequent emergence of the seedlings. In general, the speed and percentage of seed germination was greatly increased by the most treatments including hot water immersion and dry heating (germination increased up to 83%), clearly indicating that there is a physical (seed coat) dormancy in this species, while untreated seeds (i.e., control) had relatively moderate germination and emergence percentages. This positive (or damaging at high temperatures) effect of dry heat on seed germination and emergence rate and percentage, implies the potential effect of fire on promotion of V. agnus castus seed germination and in some cases it could be taken into account, as long as fire is a frequent ecological factor in Mediterranean-type ecosystems.