The present work aimed to study a breeding method for two Calendula species, the cultivated species  Calendula officinalis and the wild species  Calendula micrantha. The study was concerned with the probability of hybridization between both species to obtain a hybrid plant with attractive flowers that needs less water requirements and maintenance, to be used as a ground cover or for flowerbeds in arid and semi-arid regions. This study was carried out in the Flowers and Ornamental Plants Research Gardens at the Faculty of Agriculture, Alexandria University from 1994 to 1997.  A comparison between the two used species was carried out (growth habit, vegetative growth, flowering, carotenoid content in flowers, stomata, anthers, pollen grains, pollen fertility and relative distribution of DNA content).  Crossing between both species took place and failed to produce hybrid seeds. Results indicated that adaptation had a significant effect on the growth and flowering of the wild Calendula species. The comparison between the two Calendula species explained - to some extent - the failure of the crossing between both species regarding to their different genetical and anatomical structure.