- Name also: Shiny Geranium, Shining Geranium, Shining Crane’s-bill
- Family: Geranium Family – Geraniaceae
- Growing form: Annual or biennial herb. Taproot slightly branched, whitish.
- Height: 10–35 cm (4–15 in.). Stalk branched, fragile, almost glabrous, often reddish.
- Flower: Regular (actinomorphic), 5–8 mm (0.2–0.3 in.) wide. Petals 5, pink, round-tipped. Sepals 5, edged, wrinkled, sharp-pointed, erect, shorter than petals. Stamens 10. Pistil of 5 fused carpels, style solitary, 5 stigmas. Flowers usually in axillary pairs, or terminal on shoots.
- Leaves: In basal rosette and opposite (decussate) or solitary on stem. Rosette leaves long-stalked, stem leaves stalked–almost stalkless, stipulate. Blade round–kidney-shaped, with palmate venation, somewhat glabrous, shiny, 5-lobed (deeply); lobes broad, with shallow blunt short-tipped teeth.
- Fruit: 5-parted schizocarp, beak-like tip, beak segments coil at dehiscence. Mericarps with indistinct net-surface, finely haired especially along sides of seam.
- Habitat: Steep crags and rocky slopes, broad-leaved forests, bird rocks. Calciphile. Also nitrophile.
- Flowering time: June–August.
- Endangerment: Near threatened.
Shining cranesbill demands relatively high summer temperatures, a long growing period and a long, frost-free autumn. Even in suitable climates, however, it doesn’t grow just anywhere: typical nitrogenous soils that it clearly favours include ridges, cracks and crags on bird rocks, e.g. in Finland’s outer archipelago, where it often grows in the shade of hedges. Sometimes it also grows in the calciferous soil of the archipelago, but in such cases the growing medium has most likely been enhanced by birds’ droppings. As shining cranesbill carpels ripen they usually break off and fall to the mother plant’s roots. The species doesn’t seem to spread very efficiently over long journeys, which would explain why it has failed to establish itself in habitats that appear suitable.
Shining cranesbill can usually be easily differentiated from other small-flowered and moderately-sized members of the Geranium family – especially herb Robert (G. robertianum), small-flowered cranesbill (G. pusillum) and Dove’s foot cranesbill (G. molle) by its sparsely-haired, round, kidney-shaped leaves and its erect, edged sepals.