''Pelargonium'' 'citrosum' (often sold by the invalid

binomial name In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

''Pelargonium citrosum'' ) is a perennial

subshrub A subshrub (Latin ''suffrutex'') or undershrub is either a small shrub (e.g. prostrate shrubs) or a perennial that is largely herbaceous but slightly woody at the base (e.g. garden pink and florist's chrysanthemum). The term is often interch ...

with fragrant leaves that are reminiscent of citronella. PelargoniumCitrosum

''P.'' 'citrosum' is marketed as "mosquito plant" or "citrosa geranium" in stores in the United States and Canada, even though research from the University of Guelph indicates the plant is ineffective against ''

Aedes aegypti ''Aedes aegypti'' ( or from Greek 'hateful' and from Latin, meaning 'of Egypt'), sometimes called the Egyptian mosquito, dengue mosquito or yellow fever mosquito, is a mosquito that spreads diseases like dengue fever, yellow fever, malar ...

'' mosquitos. "Not only was the plant ineffective at protecting humans against Aedes mosquito bites, the mosquitoes were seen landing and resting on the citrosa plant on a regular basis." It is claimed that ''P.'' 'citrosum' may be a genetic bonding of the African geranium with genes from

Cymbopogon ''Cymbopogon'', also known as lemongrass, barbed wire grass, silky heads, oily heads, Cochin grass, Malabar grass, citronella grass or fever grass, is a genus of Asian, African, Australian, and tropical island plants in the Poaceae, grass famil ...

grass, but that claim has also been proven false. The plant appears to be a cultivar of ''

Pelargonium graveolens ''Pelargonium graveolens'' is a ''Pelargonium'' species native to the Cape Provinces and the Northern Provinces of South Africa, Zimbabwe and Mozambique. Common names include rose geranium,

''. The citronella geranium is not to be confused with others that are also called "

mosquito plant Mosquito plant is a common name for several plants and may refer to: * ''Azolla'' species (duckweed ferns) * '' Agastache cana'' (Texas hummingbird mint) * '' Pelargonium 'citrosum (Citrosa geranium, citronella plant) * ''Verbena officinalis ...

", nor with the group of plants also known as citronella grass, or with '' Citronella mucronata'' (Chilean Citronella). ''Pelargonium'' 'citrosum' is hardy to USDA Zone 10–11.

References

External links

''Is This Plant a Hoax?''
by Arthur O. Tucker and Michael J. Maciarello, Department of Agriculture & Natural Resources, Delaware State College
IPNI Listing

Kew Plant List
citrosum Ornamental plant cultivars {{Geraniaceae-stub