Pelargonium peltatum
(ivy geranium)

Pictures

Identity

Preferred Scientific Name

• Pelargonium peltatum (L.) L'Hér. ex Aiton

Preferred Common Name

• ivy geranium

Other Scientific Names

• Dibrachya clypeata Eckl. & Zeyh.
• Geraniospermum peltatum (L.) Kuntze
• Geranium peltatum L.

International Common Names

• English: cascading geranium; ivy-leaved geranium; ivy-leaved pelargonium
• Spanish: geranio de maceta; geranio de rastra; geranio yedra; geranios; gitanas; murcianas

Local Common Names

• Denmark: haengepelargonie
• South Africa: Kolsuring; wildemalva

Summary of Invasiveness

P. peltatum is an ornamental plant listed in the Global Compendium of Weeds as “cultivation escape, garden thug, naturalised, weed” (Randall, 2012). The species is native to South Africa but has been cultivated as an ornamental in Europe for over 300 years (Miller, 1996). P. peltatum spreads by seeds and can also be propagated by cuttings, and thrives in coastal and succulent scrublands (SANBI, 2015). The leaves of the species can reportedly cause temporary dermatitis upon touch, lasting several minutes (NCSU, 2015). The species is included in a list of adventive species in New Zealand, France and Greece, and an invasive species list of Andalucia, Spain, and has been known to escape from cultivation in Puerto Rico (Liogier and Martorell, 2000; Aedo et al., 2009; Randall, 2012).

Taxonomic Tree

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Geraniales
•                         Family: Geraniaceae
•                             Genus: Pelargonium
•                                 Species: Pelargonium peltatum

Notes on Taxonomy and Nomenclature

There has been much confusion in the literature surrounding the genera of Pelargonium and Geranium. The genus Geranium was originally described by Linnaeus in 1753 but was then divided into Pelargonium and Geranium by Charles L’Héritier in 1789, and many species from both genera have retained the name ‘geranium’ in their vernacular names. Further, many cultivars and varieties exist, many with similar variety names to other species. The genus name Pelargonium derives from the Greek word ‘pelargos’, meaning ‘stork’, in reference to the beak-like shape of the fruit, which has also resulted in the genus being called the ‘stork’s bill’ genus (Stearn, 1992).

The genus Pelargonium is divided into sections based on morphological and other features. The species Pelargonium peltatum is a member of the Ciconium section. It is the parent species of the ‘ivy leaved pelargoniums’ cultivars, since, like ivy, its leaves are shield-shaped, i.e., attached on the lower surface away from and not at the margin. The species name peltatum derives from the Latin word ‘pelta’, meaning shield, in reference to the shape of the leaves (Stearn, 1992; SANBI, 2015).

Description

SANBI (2004) gives the following description: Climbing herbaceous slender-stemmed perennial to 2 m or more; leaves succulent, peltate, entire, bluntly lobed or 5-angled, 2-7 cm in diameter, ± glabrous, some populations with downy leaves or zonation patterns; flowers (Aug-Oct mainly) borne in 2-9 flowered umbel-like inflorescences on long peduncles, mauve, pink-mauve, pale pink or almost white. Characteristic microscopic features are: the unicellular clothing hairs of leaf and stem, up to 400 µ long, thick walled, slightly warty, base swollen, surrounded by 4-5 subsidiary cells with striated cuticle; the numerous calcium oxalate cluster crystals (rosette aggregates), loose in the powdered drug or in the parenchyma of the leaf mesophyll, up to 90 µ in diameter; the glandular hairs of the leaf lamina, with unicellular heads and 4-5 celled stalks, the basal cell elongated; the small glands with unicellular stalk and unicellular head up to 40 µ in diameter; the thin-walled polygonal cells of the lower leaf epidermis with anomocytic stomata; and no underlying palisade layer. 

Plant Type

Distribution

Native to South Africa, P. peltatum has been intentionally distributed around the world for use as a flowering ornamental. The species has been present in Europe since 1700 (Miller, 1996; Royal Botanic Garden Edinburgh, 2015), and has been reported growing outside of cultivation in Spain, Greece, and the Azores (DAISIE, 2015). It is known to be adventitious in France, Greece, and New Zealand (Aedo et al., 2009), naturalized in Italy and California (Randall, 2012), and has been introduced and cultivated in the Andean region of Ecuador (Vascular Plants of Ecuador, 2015). 

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

History of Introduction and Spread

P. peltatum is native to South Africa but was introduced to Europe at the turn of the eighteenth century by the governor of Cape Province, who sent a parcel of plants to the Netherlands in 1700 (Miller, 1996; SANBI, 2015). Within a year, the species was already being grown in England by the Duchess of Beaufort, who around this time was also having other Pelargonium species such as P. zonale grown (Miller, 1996).

Date of introduction to the West Indies is uncertain, but it may have occurred recently. Geraniums were not included in Macfadyen’s (1837) flora of Jamaica or Bello’s (1881; 1883) work on Puerto Rico, but the species was included in Britton’s (1918) work on Bermuda, in which it was mentioned as “occasionally grown in flower gardens”. Subsequently it was also reportedly cultivated in flower gardens of Puerto Rico by 1924 (Britton and Wilson, 1924).

Risk of Introduction

Risk of introduction for P. peltatum is low but not insignificant, as cultivation escape and deliberate introduction could help the naturalized population to spread. The species is known to escape from cultivation in Puerto Rico (Liogier and Martorell, 2000), is an adventitious alien species in France, Greece, and New Zealand (Aedo et al., 2009; Randall, 2012), and was included in a list of invasive species in Andalucia, Spain (Randall, 2012). The species received a low risk score of 0 in a risk assessment prepared for Hawaii (PIER, 2015). 

Habitat

P. peltatum grows in scrub along the coast or on dry rocky hillsides (SANBI, 2015; PFAF, 2015). In Ecuador the species has been reported growing between 2000-3000 m (Vascular Plants of Ecuador, 2015). It is well known as a potted or garden ornamental and has been widely cultivated for this purpose since it was exported from its native South Africa at the turn of the eighteenth century (Miller, 1996).

Habitat List

Biology and Ecology

Genetics

Gametophytic count = 9, sporophytic count = 18, 36 (IPCN Chromosome Reports, 2015).

Environmental Requirements

The species grows in coastal scrublands and dry, rocky hillsides, preferring dry or moist, well-drained soil, and it is recommended to be cultivated in light (sandy) and medium (loamy) soils that can be acid, neutral, or basic in pH (PFAF, 2015; SANBI, 2015). It is drought resistant, but cannot tolerate frost or dense shade (Missouri Botanical Garden, 2015). It typically spreads up to 1 m and to heights of 1.8 m.

Climate

Soil Tolerances

Soil drainage

• free

Soil reaction

• acid
• alkaline
• neutral

Soil texture

• light
• medium

Means of Movement and Dispersal

P. peltatum has been intentionally introduced by man beyond its native South African range to various parts of the world primarily for cultivation as an ornamental plant. It is also an accidental introduction, as it has reportedly escaped in Puerto Rico (Liogier and Martorell, 2000), has been reported growing outside of cultivation in Spain, Greece, and Azores (Aedo et al., 2009; DAISIE, 2015), and is naturalized in New Zealand and California (Randall, 2012). The varying ‘ivy leaved’ cultivars were developed from P. peltatum, and are likewise widespread in cultivation.

Members of the Pelargonium genus can disperse their small seeds by wind, water, and soil. Their seeds typically possess a plume or tail-like attachment which can carry them over long distances. The attachment on the seeds of P. capitatum, for example, reportedly will essentially drill and secure the seed into soil if twisted by the wind or affected by movement of animals, and this species is considered one of the most widespread and naturally invasive of coastal weeds in the Perth region of Australia (Dixon, 2011; Western Australian Herbarium, 2014). 

Pathway Causes

Pathway Vectors

Impact: Environmental

P. peltatum has been widely distributed as an ornamental flowering plant, grown both in containers and in the ground, sometimes used by horticulturists for groundcover and proving to be economically beneficial (SANBI, 2015). However in cases where it has escaped from cultivation, the species has been reported to become weedy and has even been included in a list of invasive species in Spain (Randall, 2012). It also has a vine-like, climbing growth habit which could potentially pose competition by smothering native flora, although this has not been reported. The horticultural value of the species generally outweighs existing evidence against recommending its introduction beyond its native range of South Africa.

Risk and Impact Factors

• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Has propagules that can remain viable for more than one year

• Highly likely to be transported internationally deliberately

Uses

P. peltatum has been extensively cultivated for landscape uses and as an ornamental in botanical gardens, borders, containers, as groundcover due to its climbing habit, and, in places where it is prone to frost, indoors and in greenhouses (Walt, 1977; Miller, 1996; Wiersema and Leon, 2013; SANBI, 2004).

Medicinal uses for this species have been reported. The leaves possess an acidulous sap reportedly effective as an astringent and antiseptic for sore throats; the Afrikaans vernacular name refers to this useful sap (SANBI, 2004). Fresh juice of the leaves can be applied to oral ulcers, and leaves heated in soil can be prepared for earaches, toothaches, scratches, and minor burns (Walt, 1977; SANBI, 2004).

In some places the leaves and buds of P. peltatum, both edible, are eaten as vegetables either raw or cooked (SANBI, 2015).

A blue indigo dye is obtained from the petals and was said to have been used by Burchell in his paintings, as well as for wool or cloth dye (Walt, 1977; Miller, 1996).

Uses List

General

• Botanical garden/zoo

Human food and beverage

• Vegetable

Materials

• Dyestuffs
• Essential oils

Ornamental

• Potted plant

Prevention and Control

P. peltatum is considered a low risk species, having received a score of 0 in a recent PIER risk assessment (PIER, 2015), and has not been reported to be usually problematic. Other Pelargonium species that have proved to be weedy, however, sometimes require government assistance to stop infestations using chemicals, such as the case of P. alchemilloides, which is one of 28 plants listed in Australia’s Federal Government Alert List for Environmental Weeds (CRC for Australian Weed Management, 2003).

Gaps in Knowledge/Research Needs

Research is lacking on the potential invasiveness of P. peltatum in order to better gauge the risk of introduction and spread of the species, especially given its history as a widely dispersed cultivated ornamental species. Based on the existing literature, risk of introduction of P. peltatum is low but not insignificant, as other members of the Pelargonium genus are listed as invasive and potentially harmful to biodiversity and native flora.

References

Acevedo-Rodríguez P; Strong MT, 2012. Catalogue of the Seed Plants of the West Indies. Smithsonian Contributions to Botany, 98:1192 pp. Washington DC, USA: Smithsonian Institution. http://botany.si.edu/Antilles/WestIndies/catalog.htm

Aedo C; Estébanez B; Navarro C, 2009. Geraniaceae - Pelargonium peltatum (L.) L'Hér. Euro+Med Plantbase - the information resource for Euro-Mediterranean plant diversity. http://ww2.bgbm.org/euroPlusMed/PTaxonDetail.asp?UUID=7FD4E5A4-E24B-4DDD-AD84-5E55D868171D

Arianoutsou M; Bazos I; Delipetrou P; Kokkoris Y, 2010. The alien flora of Greece: taxonomy, life traits and habitat preferences. Biological Invasions, 12(10):3525-3549. http://www.springerlink.com/content/64p8761783323136/

Bello D, 1883. [English title not available]. (Apuntes para la flora de Puerto Rico. Segunda parte. Monoclamídeas.) Anales de la Sociedad Española de Historia Natural, 12:103-130.

Bello Espinosa D, 1881. [English title not available]. (Apuntes para la flora de Puerto Rico. Primera parte.) Anal. Soc. Española de Hist. Nat, 10:231-304.

Britton NL, 1918. Flora of Bermuda. New York, USA: Charles Scribner's Sons. 585 pp.

Britton NL, 1924. Botany of Porto Rico and Virgin Islands. Scientific Survey of Porto Rico and Virgin Islands. New York, USA: New York Academy of Sciences, 200 pp.

CRC for Australian Weed Management, 2003. Garden geranium (Pelargonium alchemilloides) weed management guide. http://www.environment.gov.au/biodiversity/invasive/weeds/publications/guidelines/alert/p-alchemilloides.html

DAISIE, 2015. Delivering Alien Invasive Species Inventories for Europe. European Invasive Alien Species Gateway. www.europe-aliens.org/default.do

Dixon K, 2011. Coastal plants: a guide to the identification and restoration of plants of the Perth region [ed. by Dixon, K.]. Collingwood, Australia: CSIRO Publishing, x + 277 pp.

IPCN Chromosome Reports, 2015. Index to Plant Chromosome Numbers (IPCN), Tropicos website. St. Louis, Missouri, USA: Missouri Botanical Garden. http://tropicos.org/Project/IPCN

Liogier HA; Martorell LF, 2000. Flora of Puerto Rico and adjacent islands: a systematic synopsis, 2nd edition revised. San Juan, Puerto Rico: La Editorial, University of Puerto Rico, 382 pp.

MacFadyen J, 1837. The flora of Jamaica: A description of the plants of that island. London, UK: Longman, Orme, Brown, Green & Longman, 351 pp.

Miller D, 1996. Pelargoniums: a gardener's guide to the species and their cultivars and hybrids. London, UK: B.T. Batsford Ltd, 175 pp.

Missouri Botanical Garden, 2014. Tropicos database. St. Louis, Missouri, USA: Missouri Botanical Garden. http://www.tropicos.org/

Missouri Botanical Garden, 2015. Missouri Botanical Garden Plant Finder. St. Louis, MO, USA: Missouri Botanical Garden. http://www.missouribotanicalgarden.org/plantfinder/plantfindersearch.aspx

NCSU, 2015. Pelargonium peltatum. Plants database., USA: College of Agriculture and Life Sciences, North Carolina State University. http://plants.ces.ncsu.edu/plants/all/pelargonium-peltatum/

PFAF, 2015. Plants For A Future. http://www.pfaf.org/user/Default.aspx

PIER, 2015. Pacific Islands Ecosystems at Risk. Honolulu, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

Randall RP, 2012. A Global Compendium of Weeds. Perth, Australia: Department of Agriculture and Food Western Australia, 1124 pp. http://www.cabi.org/isc/FullTextPDF/2013/20133109119.pdf

Royal Botanic Garden Edinburgh, 2015. Flora Europaea. Edinburgh, UK: Royal Botanic Garden Edinburgh. http://rbg-web2.rbge.org.uk/FE/fe.html

SANBI, 2004. Pelargonium peltatum herba - Medicinal Monographs., South Africa: Kirstenbosch National Botanical Garden, South African National Biodiversity Institute. http://pza.sanbi.org/sites/default/files/info_library/pelargpeltat.pdf

SANBI, 2015. South African National Biodiversity Institute plant information website., South Africa: Kirstenbosch National Botanical Garden, South African National Biodiversity Institute. http://pza.sanbi.org/

Stearn WT, 1992. Stearns dictionary of plant names for gardeners: A handbok on the origin and meaning of the botanical names of some cultivated plants. London, UK: Cassell.

USDA-ARS, 2015. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2015. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/

Vascular Plants of Ecuador, 2015. Catalogue of the Vascular Plants of Ecuador. St. Louis, Missouri, USA: Missouri Botanical Garden. http://tropicos.org/Project/CE

Walt JJAvan der, 1977. Pelargoniums of Southern Africa. Cape Town, South Africa: Purnell, 50 pp.

Western Australian Herbarium, 2014. FloraBase - the Western Australian Flora. FloraBase - the Western Australian Flora., Australia: Department of Parks and Wildlife, Western Australia. http://florabase.dpaw.wa.gov.au/

Wiersema JH; Leon B, 2013. World economic plants: a standard reference, 2nd edition. London, UK: CRC Press, 1336 pp.

Links to Websites

Contributors

2/2/2015 Original text by:

Marianne Jennifer Datiles, Department of Botany-Smithsonian NMNH, Washington DC, USA

Pedro Acevedo-Rodríguez, Department of Botany-Smithsonian NMNH, Washington DC, USA

Distribution Maps