Pelargonium is a genus of flowering plants which includes about 200 species of perennials, succulents, and shrubs, commonly known as geraniums or storksbills. Confusingly, Geranium is the correct botanical name of a separate genus of related plants often called Cranesbills. Both genera are in the Family Geraniaceae. They are drought and heat tolerant, but can tolerate only minor frosts. Some species are extremely popular garden plants, grown as bedding plants in temperate regions.

Pelargonium tetragonum commonly known as square-stemmed pelargonium is a plant adapted to grow in dry habitats (xerophyte). It branches from the base and if supported by other vegetation, will reach a height of 2 m. The plant tends to sprawl, but can be successfully grown as a pot specimen. Pelargonium tetragonum is distinguished by its almost leafless, three- to four-angled, jointed and succulent stems. When present, the leaves are fleshy, palm-shaped and sometimes have red zonal markings. The, very attractive, cream to pink flowers occur in pairs on the flower stem. Each flower has four petals, with the upper two significantly larger than the lower pair. The large upper petals are streaked with red. The flowering time is from September to December. Unlike many other pelargoniums, this species does not produce aromatic oils. However, the attractive flower and unusual growth form make this a worthwhile addition to any pelargonium collection.