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Products > Geranium Rozanne ['Gerwat']
Geranium Rozanne ['Gerwat'] - Rozanne Geranium
Image of Geranium Rozanne ['Gerwat']
[2nd Image]
Habit and Cultural Information
Category: Perennial
Family: Geraniaceae (Geraniums)
Origin: Garden Origin
Flower Color: Blue Violet
Bloomtime: Summer/Winter
Synonyms: [G. 'Jolly Bee']
Parentage: (G. wallichianum 'Buxtons Variety' x G. himalayense)
Height: 1-2 feet
Width: 2-3 feet
Exposure: Sun or Shade
Irrigation (H2O Info): Medium Water Needs
Winter Hardiness: < 0 F
Geranium Rozanne ['Gerwat'] - A vigorous perennial that forms a compact bushy clump to 18 to 20 inches tall by over 2 feet wide (in favorable conditions spreads much wider) with lightly chartreuse marbled deep-green leaves that are deeply cut into 5 lobes and are about 1 inch long by nearly 2 inches wide in outline. From mid-June continuing until the first frost appear an abundance of 2 to 2 1/2-inch-wide flowers, that are a deep violet blue (RHS 90a) toward the petal tips and transition inward to pale violet blue (RHS 92d) and finally to white in the center with purple veins prominently displayed within the lighter sections and with dark anthers dancing above the petals.

Plant in full sun to part sun - though requiring 2-3 hours of sun to bloom well, it is recommended that this plant be planted with afternoon shade in hotter climates. Soil should be well-drained with regular to occasional irrigation. This plant is hardy to USDA Zone 5 (and in cooler climates foliage will turn reddish in fall). The Perennial Plant Association recommends cutting back this plant in late summer to help it maintain a neater shape. A great plant for mass plantings, border highlights and containers.

Geranium Rozanne originated as the speculated cross between Geranium wallichianum 'Buxtons Variety' and an unnamed cultivar of Geranium himalayense. It was selected by George and Rozanne Waterer in their garden in Somerset, England for its compact bushy habit with deeply divided green leaves and profuse and continuous long-season production of large white-centered violet-blue flowers. It was noted that the flowers of 'Rozanne' are similar in shape to the Geranium wallichianum seed parent but are larger and have purple-veined white centers, and the foliage is more like the pollen parent, Geranium himalayense. It was introduced through the Blooms of Bressingham program in 2000 and was declared the Perennial Plant Association's Plant of the Year for 2008. The cultivar name used to file for Plant Breeders Rights in Europe and its US Plant Patent, which it received in October 2001, is 'GERWAT' (using the GER of Geranium and WAT from the originators name Waterer) and this remains the official cultivar name for this plant, though usually it is listed simply as "Rozanne". This plant received US Plant Patent PP12,175, which has since expired. A similar plant introduced around the same time that led to some amount of controversy and legal issues was called Geranium 'Jolly Bee'.

The etymology of the genus name Geranium, and the family Geraniaceae, is derived from the Greek word, 'geranos' which means "crane" from the seed capsule's resemblance to beak of this bird. It is a large genus with over 430 species distributed throughout most of the world, except in lowland tropical areas. 

This information about Geranium Rozanne ['Gerwat'] displayed on this web page is based on research we have conducted in our horticultural library and from reliable online resources. We also will relate observations we have made about it as it grows in our nursery gardens and other gardens visited, as well how our crops have performed in containers in the nursery field. Where appropriate, we will also incorporate comments that we receive from others and we welcome hearing from anyone with additional information, particularly if they can share cultural information that would aid others in growing this plant.