ABSTRACT
This chapter describes the classification used for plants, how their botanical and horticultural names are applied and investigates some plant groups of importance to horticulture. Taxonomy is the study of the principles and practices on which classification is based that is, the systems and methods used to classify organisms. Classification is the process of assigning organisms to groups. Nomenclature is the process of devising names for organisms. Plant classification has varied over time with people increasing knowledge and this has led to a number of systems being used which vary primarily according to the rank allocated to different plant groups. Different systems have been favoured by different countries. In addition terms Angiospermae and Anthophyta have been used widely but do not have a position in the taxonomic hierarchy. In the classification hierarchy, cultivar is a subgroup of species and is equivalent to subspecies, varietas and forma but the cultivar name always follows these in order.
