Common red garden geranium.
A geranium is any of the 230 species of perennial, succulent, and shrub plants of the genus Pelargonium. Confusingly, the scientific name of the cranesbills is Geranium, and both genera are in the family Geraniaceae. (Linnaeus originally put both genera in one, and they were only separated in 1789 by Charles LÒHéritier.)
Geranium leaves are usually alternate, and palmately lobed or pinnate, often on long stacks, and sometimes with light or dark patterns. The erect stems bear five-petaled flowers in umbel-like clusters called pseudoumbels. The shapes of the flowers have been bred to a variety ranging star-shaped to funnel-shaped, and colors include white, pink, red, orange-red, and fuchsia.
Horticultural geraniums fall into six major groups, with zonals subdivided further:
- Regal or Martha Washington
- Zonal - erect and bushy
- Formosum hybrid