Agapanthus come from South Africa and are herbaceous perennials belonging to the family Agapanthaceae which contains six species and a number of subspecies, some hardy and some tender, but all essentially producing a rootstock with an abundance of thick fleshy roots and mainly tight crowns of buds, strap shaped leaves, and umbels of mainly blue flowers. Not strictly bulbous but rhizomatous, they have for a long time featured in bulb catalogues.
From a horticultural point of view, Agapanthus are in two main groups, deciduous and evergreen. The evergreen ones come from the western Cape and parts of the eastern Cape where winter rains predominate. They appear to be more tolerant of summer drought and make the wiser choice for the “Mediterranean” type planting schemes on hot dry exposed slopes and in containers, and will withstand lack of water for longer periods. The deciduous species are mainly from the summer rainfall areas. Winter wet in our UK gardens seems not to bother them at all, providing the drainage is good. In this group the leaves die readily by late autumn and the crown of buds remains hidden below the surface of the soil. Most of the deciduous plants in cultivation will be derived from A. campanulatus, while the evergreen ones are from A. praecox.