The Southern Swallowtail is mostly found on warm, dry calcareous slopes with flower-rich vegetation and low-growing bushes. The butterflies prefer slopes that are steep and rocky. They are especially active during the hottest hours of the day. Different foodplants are known, all of them umbellifers. Ptychotis saxifraga is the most important one in the western part of its range, but eggs are also laid on Opopanax chironium, Seseli montanum and Trinia glauca. In the Eastern part, the caterpillars feed mostly on various fennels (Ferula spp.) and also on Opopanax hispidus, Burnet saxifrage (Pimpinella saxifraga), Scaligeria cretica and Wild Parsnip (Pastinaca sativa). The caterpillars eat the flowers and ripening seeds. They seem to prefer plants growing in very sparse vegetation near bare patches. The Southern Swallowtail has one generation a year and passes the winter in the pupal stage. Habitats: phrygana (40%), sclerophyllous scrub (20%), heath and scrub (20%), dry calcareous grasslands and steppes (10%), dry siliceous grasslands (10%).