Geranium macrorrhizum is a species of hardy flowering herbaceous perennial plant in the genus Geranium, Geraniaceae family. It is native to the South east Alps and the Balkans.<ref>Template:Cite book</ref> Its common names include bigroot geranium,<ref name=GRIN>Template:GRIN</ref> Bulgarian geranium,<ref name=GRIN/> and rock crane's-bill.<ref name=BSBI07>Template:Cite web</ref>
It has five-lobed (palmate) leaves that are aromatic when crushed, with pale pink flowers in summer. It is cultivated as an ornamental plant in temperate regions, where it is used as a flowering groundcover, with named cultivars selected for flower colors from white through pink to magenta. The cultivar 'Ingwersen's Variety' (pale pink)<ref>Template:Cite web</ref> has gained the Royal Horticultural Society's Award of Garden Merit.<ref>Template:Cite web</ref>
The plant is used for medical purposes in the traditional herbal medicine since it possesses high antimicrobial <ref>Niko S Radulović, Milan S Dekić, Zorica Z Stojanović-Radić, Suad K Zoranić. Geranium macrorrhizum L. (Geraniaceae) essential oil: a potent agent against Bacillus subtilis. Chemistry biodiversity (2010). Volume: 7, Issue: 11, Pages: 2783-2800</ref> properties. Essential oil is prepared from it so it is also used in aromatherapy. In Bulgaria an oil is extracted from this plant, the name of which in Bulgarian means 'the healthy one'. In addition to essential oil, it contains flavonoids, sesquiterpenes, phenolic acids, pigments, vitamins, and mineral salts. A major component of essential oil is the sesquiterpene ketone germacrone.