The aim of this thesis is to determine barriers to interspecific hybridisation in selected Limonium species. Production of new commercially viable hybrids is essential to the development of the Limonium cut flower market. Very few studies have been published with respect to pollination and post-pollination biology of this genus so this study contributes a better understanding of events leading to fertilization and some of the factors involved in interspecific hybrid production. The thesis initially introduces the genus and its cultivation. Later chapters involve aspects of post-pollination biology and determination of normal development associated with fertilization, including pollen tube growth, ovary and ovule growth and embryo production. This information is used to judge the success, barriers and problem associated with new hybrid Limonium production. Interspecific hybrids were not obtained, but the information provided serves to highlight difficulties in hybrid production and provides opportunities for more directed breeding programmes.