Technical Abstract: This review paper will appear as a chapter in a book entitled Flower Breeding and Genetics published by Kluwer Academic Press. Thus chapter describes the garden petunia. The garden petunia is a complex hybrid involving at least two species- P. axillaris and P. integrifolia. the history of petunia improvement is summarized. There has been significant taxonomic confusion as to the correct names of the taxa, as well as the inter-taxa relationships. Even in the recent literature, the same taxon has described under various names. This paper should help clear-up the confusion. Petunia has also been extensively used as a model lant of the study of flower color and tissue culture. Finally, the flower color and tissue culture literature is reveiwed and discussed.