Botanists have divided the entire world into just six floral kingdoms. South Africa's Western Cape has one all to itself - that's 0.04 percent of the surface of the planet. The largest, the Boreal covers 42 percent of the earth.
So they take this tiny patch of land, covering 90,000 sq km (34,850 sq miles) from the Cederberg Mountains in the west to Port Elizabeth in the east very seriously. And so they should. Because it has an astounding 8,500 species of plants. That's 42.5 percent of all the species found in Southern Africa. On Table Mountain alone, there are 1,470 - more than in the whole of the British Isles.
Most of them are not big and showy. You have to look hard to see the differences. Together they may up a type of mountain scrubland known as 'fynbos' (fine bush) - fine-leaved, evergreen plants that can survive the poor soil, hot summers and wet winters. There are reeds, ericas (related to heathers), grasses and bulbs such as strelizias, freesias, pelargoniums, campanulas, lobelias and gladioli which have become common garden flowers around the world. However the kings of the fynbos are undoubtedly the proteas which come in an infinite variety of styles and colours but are best known for the heavy furry pink and black flowers that have become the national symbol of South Africa.
Once upon a time - well, about 3 million years ago - the whole region had a warmer climate and was covered in lush subtropical forest. Some died out naturally, much was cleared by settlers for farming and building. The glorious yellowwood and stinkwood trees which once soared in the tangled woodlands now gleam as Cape Dutch floors as furniture. Now only isolated pockets of virgin forest remain in Knysna and Tsitsikamma on the Garden Route. Tucked into the undergrowth, carefully protected are some of the oldest plants on the planet - cycads, which are said to be unchanged since the Jurassic era 150-200 million years ago. These plants were around at the same time as the dinosaurs.
Bizarrely, it's left to the Cape's desert areas to be the flashiest and really show off. Throughout the year, there are interesting things to see here, botanically speaking, such as the extraordinary quiver tree that dots the landscape of the Northern Cape. But with the spring rains in September and October the desert quite literally bursts into life.
The Karoo, stretching east, is a gentler palette of yellow, purple and white. In the west, mesembryanthemums and Namaqualand daisies burst into a psychadelic riot of colour that paint great swathes of the landscape in hot pinks, purples and orange. There are flower hotlines and traffic jams build up as people flock north to see the sight.
No one has ever managed a complete layman's guide to Cape flowers. Once there, the best place to start is at the Kirstenbosch Gardens, which are one of the greatest botanical gardens in the world - allow at least half a day. There are also various local tours to see the flowers or you can hire a car and drive yourself.
Flower line: 083-910 1028 (June-October).