H. graecum is only known from the Cyclades and doubtfully from western Crete. It grows on rocky soils, under scrubs, in dry meadows, along roads and at the seaside. H. laconicum is limited to the central and south-eastern Peloponnesos, in particular the Mainalo, Parnon and Taygetos mountains and the surrounding lowlands. It grows at altitudes of 5-1300 m in shrubland on stony soils, field margins and meadows.