D.Don
Description
Geranium wallichianum is a perennial cranesbill native to the Himalaya and adjacent mountain systems, distributed from Afghanistan and Pakistan through northern India (Kashmir, Himachal Pradesh, Uttarakhand) to Nepal, Bhutan, and southwestern China. It inhabits alpine and subalpine meadows, forest margins, open shrublands, and grassy slopes at elevations of 2,000–4,000 m, frequently forming extensive patches in disturbed and grazed areas. The species has been documented near Kunol in the Garhwal Himalaya at 2,650 m, where it flowers late into the autumn season in October.
The plant is a spreading to trailing perennial herb with a thick, woody rootstock and procumbent to ascending stems 20–60 cm long, covered in retrorse or patent hairs. Leaves are long-petiolate, orbicular in outline, 5–10 cm in diameter, deeply palmately divided into five to seven rhombic, further lobed and toothed segments. The flowers are large and showy, 3–4 cm in diameter, borne singly or in pairs on long, glandular-hairy pedicels. Petals are five, broadly obovate, typically violet-blue to lavender with a conspicuous white centre and darker veins radiating from the base. Stamens are ten with dark anthers. The fruit is a schizocarp with a persistent beak (rostrum) 2–3 cm long; at maturity the five mericarps separate elastically, each retaining a single seed.
Geranium wallichianum is among the most horticulturally significant Himalayan cranesbills, widely cultivated in temperate gardens worldwide since the nineteenth century. The cultivar 'Buxton's Variety' (syn. 'Buxton's Blue'), selected for its clear blue flowers with prominent white eyes, has received the Royal Horticultural Society's Award of Garden Merit and remains one of the most popular autumn-flowering hardy geraniums. In its native range, the species is ecologically important as a ground-cover plant that stabilizes soil on slopes and provides late-season nectar for pollinators. It is named after the Danish botanist Nathaniel Wallich, who collected extensively in Nepal and India.
Author: D.Don · Sources: POWO (Kew), GBIF, Flora of China Vol. 11, Yeo: Hardy Geraniums (2002), Annotated Checklist of the Flowering Plants of Nepal