Pelargonium × hortorum /ˌpɛlɑːrˈɡoʊniəm/
Common name: Zonal geranium · Garden geranium · Horseshoe geranium
Pelargonium × hortorum is a hybrid group of evergreen subshrubs derived mainly from Pelargonium zonale and Pelargonium inquinans, both native to southern Africa. It is the familiar "geranium" of window boxes and summer bedding, with rounded, often dark-horseshoe-banded leaves and dense heads of red, pink, white, or salmon flowers. It is cultivated worldwide as a container and bedding plant for its long flowering season and easy care.
Care summary
Sun
Full sun to light shade
Water
Moderate; let soil dry slightly between waterings
Soil
Well-drained, fertile potting mix
Hardiness
Zones 10–11; grown as annual elsewhere
Mature height
About 30–60 cm (1–2 ft)
Pet safe
No; toxic to cats and dogs
Difficulty
Easy
Propagation
Stem cuttings are the standard method. Take 8-10 cm tip cuttings, strip the lower leaves, allow the cut to callus for a few hours, and root them in a free-draining, just-moist mix at warm room temperature; they typically root within two to four weeks. Seed-raised strains are also widely available.
Fun facts
- Though commonly called "geraniums," pelargoniums are a different genus; the confusion dates to when Linnaeus grouped them together.
- The name "zonal" refers to the darker horseshoe-shaped band on many cultivars' leaves.
- Pelargoniums were introduced to Europe from South Africa in the 17th century via the Dutch East India trade routes.
- Deadheading spent flower clusters keeps plants blooming continuously from spring until frost.