# Geranium
**Geranium** is a genus of about 337 accepted species of annual and perennial herbs in the family [Geraniaceae](https://www.edgepedia.org/geraniaceae), known commonly as cranesbills for the beak-shaped fruit. The genus was first published by Linnaeus in *Species Plantarum* in 1753, and its native range spans temper and subtropical regions to tropical mountains worldwide.[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A327764-2) It is the largest genus in its family, with roughly 350 species, ahead of *Pelargonium* with about 280.[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information)
| Key fact | Detail |
|---|---|
| Scientific name | *Geranium* Tourn. ex L., first published in Sp. Pl.: 676 (1753)[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A327764-2) |
| Species count | 337 accepted species per Plants of the World Online; ca. 350 per the Kew family treatment[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A327764-2) • [2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information) |
| Native range | Temperate and subtropical to tropical mountains, on every continent except Antarctica[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A327764-2) |
| Fruit | A schizocarp with five 1-seeded, awned mericarps that separate elastically from a central beak, the source of the name cranesbill[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information) |
| Flowers | Actinomorphic (radially symmetrical), with 5 sepals, 5 petals, and 10 stamens[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information) • [3](https://pmc.ncbi.nlm.nih.gov/articles/PMC9049363/) |
| Common confusion | The bedding plants sold as "geraniums" are usually *Pelargonium*, a separate genus since 1789[3](https://pmc.ncbi.nlm.nih.gov/articles/PMC9049363/) • [4](https://gardenuk.co.uk/plants/geranium-vs-pelargonium-difference/) |
| Seed dispersal | Explosive; in *G. maculatum* seeds are thrown an average of 3 m and up to 9 m[5](https://research.fs.usda.gov/feis/species-reviews/germac) |
## Description
Geraniums are annual or perennial herbs with stipules and leaves that are pinnately or palmately lobed or compound, arranged alternately or oppositely.[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information) The flowers are usually bisexual and radially symmetrical, with five sepals and five free petals. Fertile stamens number 10 in *Geranium*, in two whorls, a count that separates the genus from *Erodium*, which has five.[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information) Leaf venation is usually palmate in *Geranium* and pinnate in *Erodium*.[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information)
The fruit is the family's most distinctive structure: a schizocarp with five one-seeded, awned mericarps that separate elastically from a central beak. The elongate styles are hygroscopically active and curl when exposed to water, releasing the seeds; this beaked carpel gives the genus its common name, cranesbill.[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information) • [6](https://web.stanford.edu/group/dahlia_genetics/geraniums/geranium_info.htm)
## Geranium versus Pelargonium
Geranium and [Pelargonium](https://www.edgepedia.org/pelargonium) were treated as one genus until the late 18th century. The shared feature was the crane's-bill-shaped seed container, from the Greek *geranos*, crane. The decisive difference is flower symmetry: *Geranium* species have actinomorphic flowers, while *Pelargonium* flowers are zygomorphic.[3](https://pmc.ncbi.nlm.nih.gov/articles/PMC9049363/) In 1789 the French botanist Charles L'Héritier de Brutelle separated *Pelargonium* into its own genus on this basis, along with a nectar tube absent from true geraniums.[4](https://gardenuk.co.uk/plants/geranium-vs-pelargonium-difference/)
The common name nevertheless stayed with the popular garden plant. The bedding and balcony plants most people call geraniums are *Pelargonium* species, mostly native to southern Africa, and nurseries had established "geranium" as the trade name before the botanical distinction reached gardeners.[3](https://pmc.ncbi.nlm.nih.gov/articles/PMC9049363/) • [7](https://animals.sandiegozoo.org/plants/geranium-pelargonium) Other visible differences follow the split: *Pelargonium* flowers have two upper petals differing in color and pattern from the three lower ones and two to seven fertile stamens, while *Geranium* flowers have five equal petals and 10 or more stamens. *Pelargonium* seeds carry a plumed end that lets them float on the breeze; *Geranium* seeds lack the plume and are flung from the plant.[7](https://animals.sandiegozoo.org/plants/geranium-pelargonium)
## Distribution and habitat
The genus is native across temperate and subtropical regions and tropical mountains, from Alaska and [Greenland](https://www.edgepedia.org/greenland) to [Tierra del Fuego](https://www.edgepedia.org/tierra-del-fuego), and from Iceland to New Zealand; Kew lists native occurrences in well over 200 regions and introduced populations in places such as Sri Lanka, Réunion, and the [Falkland Islands](https://www.edgepedia.org/falkland-islands).[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A327764-2) In the Neotropics, *Geranium* occurs in most major mountains of tropical America and some dry coastal areas, but is absent from lowland tropical forest.[2](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information) Some species reach oceanic islands as distant as Madeira and Hawaii.[8](https://www.botanic.cam.ac.uk/the-garden/horticultural-collections/national-plant-collections/geranium-species-primary-hybrids/)
The genus remains taxonomically active. Carlos Aedo's monograph of *Geranium* (2023, CSIC Madrid, 898 pages) is the current reference work, and new species continue to be described; a 2025 study reported *Geranium swatense* as new to India and assessed it as endangered or vulnerable.[9](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A322493-2) • [10](https://doi.org/10.1002/fedr.70005)
## Reproduction and seed dispersal
Geranium flowers are visited by insects of many kinds and sizes, which serve as pollinators.[11](https://www.tandfonline.com/doi/pdf/10.1080/0028825X.1985.10434228) In the North American woodland herb *Geranium maculatum*, plants are self-compatible but depend on pollinators for seed set, and young plants usually first bloom in their second or third year.[5](https://research.fs.usda.gov/feis/species-reviews/germac) Experimental work in central Illinois populations tested whether seed production is limited by pollen delivery, comparing supplementarily pollinated flowers with controls receiving natural pollination.[12](https://pubmed.ncbi.nlm.nih.gov/28313048/)
[Seed dispersal](https://www.edgepedia.org/seed-dispersal) is explosive. As the dried fruit splits, the mericarps are thrown from the plant; in *G. maculatum* the measured average dispersal distance is 10 feet (3 m), with a maximum of 30 feet (9 m).[5](https://research.fs.usda.gov/feis/species-reviews/germac) Studies of *G. molle* suggest the mechanism favors maximizing dispersal distance.[13](https://edepot.wur.nl/5345)
## Cultivation
Hardy geraniums are long-lived, easy-to-grow border plants suited to cottage-garden plantings. The [Royal Horticultural Society](https://www.edgepedia.org/royal-horticultural-society) notes that *G. 'Orion'* and *G. clarkei* 'Kashmir White' tolerate most soils including heavy clay; *G. macrorrhizum*, *G. nodosum*, and *G. phaeum* do well in dry, shaded spots; and small rock-garden types such as *G. dalmaticum* and *G. cinereum* 'Ballerina' want free-draining sites. Two Canary Island natives, *G. maderense* and *G. palmatum*, need frost-free winter protection.[14](https://www.rhs.org.uk/plants/geranium) Cambridge University Botanic Garden holds a national plant collection of *Geranium* species and primary hybrids, and recent RHS trials have awarded the [Award of Garden Merit](https://www.edgepedia.org/award-of-garden-merit) to top-performing entries.[8](https://www.botanic.cam.ac.uk/the-garden/horticultural-collections/national-plant-collections/geranium-species-primary-hybrids/)
## Medicinal interest
*Geranium* species have a long record of ethnomedicinal use across many countries, and reviews catalog phytochemical compounds and reported pharmacological activities, presenting the genus as a resource for drug discovery research.[15](https://pmc.ncbi.nlm.nih.gov/articles/PMC10873751/) *G. maculatum* was used as a medicinal plant in eighteenth-century North America after its introduction to cultivation.[16](https://api.pageplace.de/preview/DT0400.9780203216538_A23624055/preview-9780203216538_A23624055.pdf) Aromatic oils sold as "geranium oil" come not from this genus but from scented *Pelargonium* leaves, whose main constituents include citronellol, geraniol, eugenol, and pinene.[7](https://animals.sandiegozoo.org/plants/geranium-pelargonium)
## References
1. [Geranium Tourn. ex L., Plants of the World Online, Kew Science](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A327764-2)
2. [Geraniaceae Juss., Plants of the World Online, Kew Science](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A30001521-2/general-information)
3. [The variability of nuclear DNA content of different Pelargonium species estimated by flow cytometry, PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC9049363/)
4. [Geranium vs Pelargonium: The Difference, Garden UK](https://gardenuk.co.uk/plants/geranium-vs-pelargonium-difference/)
5. [Geranium maculatum, spotted geranium, US Forest Service FEIS species review](https://research.fs.usda.gov/feis/species-reviews/germac)
6. [Stanford Geranium Project, taxonomic history and fruit morphology](https://web.stanford.edu/group/dahlia_genetics/geraniums/geranium_info.htm)
7. [Geranium (Pelargonium), San Diego Zoo Animals & Plants](https://animals.sandiegozoo.org/plants/geranium-pelargonium)
8. [Geranium (species & primary hybrids), Cambridge University Botanic Garden](https://www.botanic.cam.ac.uk/the-garden/horticultural-collections/national-plant-collections/geranium-species-primary-hybrids/)
9. [Geranium pratense L., Plants of the World Online, Kew Science](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A322493-2)
10. [Hurrah et al. (2025). Notes on the Taxonomy, and Conservation Status of Geranium swatense. Feddes Repertorium 136(2): 128-135](https://doi.org/10.1002/fedr.70005)
11. [Reproductive biology of Geranium sessiliflorum, New Zealand Journal of Botany](https://www.tandfonline.com/doi/pdf/10.1080/0028825X.1985.10434228)
12. [Determinants of seed production in Geranium maculatum, PubMed](https://pubmed.ncbi.nlm.nih.gov/28313048/)
13. [Seed dispersal mechanism of Geranium molle, Wageningen UR e-depot](https://edepot.wur.nl/5345)
14. [Introducing geraniums, RHS Plant Guide](https://www.rhs.org.uk/plants/geranium)
15. [The geranium genus: ethnomedicinal uses, phytochemical compounds, and pharmacological importance, PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC10873751/)
16. [Geranium and Pelargonium: The Genera Geranium and Pelargonium, Routledge preview](https://api.pageplace.de/preview/DT0400.9780203216538_A23624055/preview-9780203216538_A23624055.pdf)
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*Topic: Encyclopedia › Life and health › Plants and algae › Seed plants › Other flowering plants › Rosids*
*Initially written Sep 17, 2026 · Reviewed: Sep 30, 2026; Oct 21, 2026 · Edited: Sep 30, 2026; Oct 21, 2026 · Last review: Oct 21, 2026*
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License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license