Geranium Flowers

Type of Flowers

Geranium:

Geranium is a genus of 422 species of flowering annual, biennial, and perennial plants that are commonly known as the cranesbills. They are found throughout the temperate regions of the world and the mountains of the tropics, but mostly in the eastern part of the Mediterranean region. The long, palmately cleft leaves are broadly circular in form. The flowers have five petals and are coloured white, pink, purple or blue, often with distinctive veining. Geraniums will grow in any soil as long as it is not waterlogged. Propagation is by semiripe cuttings in summer, by seed, or by division in autumn or spring.

The genus English name "cranesbill" derives from the appearance of the fruit capsule of some of the species. Species in the Geranium genus have a distinctive mechanism for seed dispersal. This consists of a beak-like column which springs open when ripe and casts the seeds some distance. The fruit capsule consists of five cells, each containing one seed, joined to a column produced from the centre of the old flower. The common name cranesbill comes from the shape of the unsprung column, which in some species is long and looks like the bill of a crane. Many species in this genus do not have a long beak-like column.

Confusingly, "geranium" is also the common name of members of the genus Pelargonium (sometimes known as 'storksbill'), which are also in the Geraniaceae family. These are generally half-hardy plants which are either grown from seed every year, or offered as bedding in spring and discarded after flowering. Linnaeus originally included all the species in one genus, Geranium, but they were later separated into two genera by Charles L’Héritier in 1789. Other former members of the genus are now classified in genus Erodium, including the plants known as filarees in North America. 

The term "hardy geranium" is often applied to geraniums to distinguish them from the pelargoniums. However, not all geranium species are winter-hardy.

The shape of the flowers offers one way of distinguishing between the two genera Geranium and Pelargonium. Geranium flowers have five very similar petals, and are thus radially symmetrical (actinomorphic), whereas pelargonium flowers have two upper petals which are different from the three lower petals, so the flowers have a single plane of symmetry (zygomorphic).