SAXIFRAGA

Hailing from arctic-alpine ecosystems these "rockfoils" make attractive rockery and groundcover plants in more temperate habitats.

Cambridge University Botanic Garden holds the UK's national collection. The half-dozen native species include purple saxifrage, S. oppositifolia, found in the Scottish Highlands and Yorkshire Dales and meadow saxifrage, S. granulata, scattered and becoming rarer because of improved grassland.

The "true" London Pride, S x urbium, not native, is believed to be a hybrid between Pyrenean S. umbrosa and Irish S. spathularis.

Genus of over 480 species of mostly mat- or cushion-forming, evergreen, semi-evergreen or deciduous perennials and biennials from mountains in the northern hemisphere.