The flora of the Verdon

The secret of this richness can be summed up in one sentence: the Verdon is a crossroads. The Mediterranean climate, warm and dry, meets the alpine influence there, cooler and mountainous. Add to this a mosaic of habitats — limestone cliffs, scree, forests, dry grassland, riverbanks. The result: the Parc du Verdon shelters some 2,200 plant species, around a third of all French flora, on less than 2,000 km². Some live only in the Verdon or in the Southern Alps alone.

If only one plant could be remembered, it would be this one. The Verdon spleenwort (Asplenium jahandiezii) is a small fern a few centimetres long that grows nowhere else on the planet except in the gorges of the Verdon. Discovered in 1911, it clings to shady spots, in the cracks and beneath the overhangs of the limestone cliffs. A strict endemic, protected at national level and classed as near-threatened, it is the living symbol of what makes the canyon irreplaceable — and one more reason to respect its cliffs.

The cliff face is not a mineral desert: it is a vertical garden. Alongside the Verdon spleenwort live Bertoloni’s columbine, the blue flower of the cool scree, and the grey sandwort, a Provence endemic with a tiny range. The Phoenician juniper also clings there, a shrub so slow-growing that some specimens are several centuries old, even a thousand years old: near the Imbut, one of them has been dated at more than a thousand years old. On the ridges and limestone grassland grow the genêt de Villars and the rare raiponce de Villars. All these species are fragile treasures, adapted to an extreme environment.

Descending from the cliff, the vegetation is organised by altitude and aspect. The floor and slopes of the middle Verdon are covered with downy oak woodland (the white oak) mixed with Scots pine. On the warm, sun-facing slopes, at low altitude, grows the holm oak (the ilex), the Mediterranean tree par excellence; conversely, on the cool, shaded slopes and at altitude, beech woods appear. Everywhere, box, junipers and broom form the undergrowth.

Lower down and drier still stretches the garrigue — thyme, rosemary, wild lavender — while the dry limestone grassland, rich in flowers, is the domain of wild orchids. At the gateway to the Verdon, finally, the great lavender fields of the Valensole plateau make up the most famous cultivated landscape in Provence.

This exceptional flora lies at the heart of several Natura 2000 sites — the Grand Canyon and the Basses Gorges — whose limestone cliffs and dry grassland are habitats of European interest. The Verdon spleenwort and Bertoloni’s columbine are among the species that justified this designation. The main danger to the cliff plants is a paradoxical one: opening new climbing routes can destroy their micro-habitats — the cliff face is alive. Elsewhere, the ubiquitous box is suffering from the box tree moth, an invasive moth from Asia.