Range & Status
Native; Oceanic, southern-temperate species: France, Spain, Portugal, Channel Islands and a few localities in Britain where it is rare.
It has been found at two sites in Cornwall, but only one is extant. It was discovered near Cape Cornwall (SW33), in West Cornwall, during the nineteenth century and remains at one site near Sladesbridge (SW97), in East Cornwall.
Habitat & Ecology
A perennial plant, it is restricted to two adjacent railway-cuttings, both on steep, rocky slopes, with a southerly aspect, on thin soils overlying acid rocks. It grows in clearings amongst scrub. The population has fluctuated with management.
Threatened by rapid scrub and tree encroachment at its Cornish locality. Hybridization with Trailing St. John' s-wort H. humifusum is another possible threat.
Recent scrub clearance work has assisted its survival in Cornwall, but Bramble Rubus fruticosus agg. has taken over cleared areas. This shows the need for ongoing management.