# Citronella essential oil > A bright, lemony-grassy single oil steam-distilled from citronella grass, a familiar scent from outdoor candles and patio blends. Canonical page: https://essential-oils.club/oils/single/citronella Type: Single oil ## At a glance - **Botanical name:** Cymbopogon nardus - **Plant part:** Grass - **Extraction:** Steam-distilled - **Aroma:** Bright, lemony, grassy - **Origin:** Sri Lanka - **Blends with:** Lemongrass, lemon ## Composition (GC-MS research aggregate) Based on 22 GC-MS samples from 13 peer-reviewed papers (2020–2026); Strong evidence base. 102 compounds reported in total. Typical share of the oil (median, with interquartile range): | Compound | Class | Median % | IQR % | Max % | Papers | |---|---|---|---|---|---| | citronellal | Oxygenated monoterpene | 26.23 | 15.23–32.16 | 61.9 | 12 | | geraniol | Oxygenated monoterpene | 21.59 | 18.55–33.86 | 42.13 | 10 | | citronellol | Oxygenated monoterpene | 12.21 | 5.78–13.48 | 17.9 | 10 | | limonene | Monoterpene hydrocarbon | 3.87 | 3.2–6.26 | 23.1 | 10 | | elemol | Oxygenated sesquiterpene | 2.46 | 0.15–6.55 | 7.55 | 8 | | neral | Oxygenated monoterpene | 2.12 | 0.53–3.75 | 10.31 | 6 | | geranyl acetate | Oxygenated monoterpene | 1.77 | 1.59–2.43 | 4.97 | 6 | | β-elemene | Sesquiterpene hydrocarbon | 1.73 | 1.15–2.59 | 5.2 | 6 | | germacrene d | Sesquiterpene hydrocarbon | 1.22 | 0.94–2.32 | 7.9 | 7 | | δ-cadinene | Sesquiterpene hydrocarbon | 1.19 | 0.68–2.41 | 12.25 | 7 | | β-caryophyllene | Sesquiterpene hydrocarbon | 1.07 | 0.9–2.14 | 8.24 | 7 | | geranial | Oxygenated monoterpene | 1.28 | 0.68–4.88 | 13.37 | 5 | Chemotypes seen in the samples: citronellal (64% of samples), geraniol (27% of samples). ## Key constituents - **Citronellal** (30-45%) — The dominant compound; responsible for citronella's sharp, lemony-fresh scent and insect-repellent reputation - **Geraniol** (20-25%) — A rosy-floral alcohol that softens the sharpness of citronellal - **Citronellol** (10-15%) — A related alcohol adding to the soft, citrus-floral undertone ## How to use it - **In the diffuser:** 3–5 drops for a fresh, energizing porch or patio atmosphere. - **With citrus grasses:** Pairs naturally with lemongrass and lemon for a citrus-grass blend. - **On skin:** Dilute in a carrier oil and patch-test — it can be sensitizing. ## Safety - Dilute in a carrier oil and patch-test first — citronella can be sensitizing for some skin types. - Maximum dermal use: Dilute in a carrier oil for skin. - Generally well tolerated, but its citronellal and geraniol are recognised fragrance allergens — dilute and patch-test, especially on sensitive skin. - Not phototoxic. Keep out of reach of children. ## What the research says - Citronella oil has been studied for antifungal and insect-repellent activity in the laboratory and field. Its use as a natural mosquito deterrent is well known, though effect tends to be shorter-lived than synthetic repellents. — JEOB study (2021) (https://doi.org/10.1080/0972060x.2021.1942231) ## Evidence - Citronella is a citronellal- and geraniol-rich grass oil, the chemistry behind both its fresh-lemony aroma and its studied antifungal and repellent activity. — JEOB study (2021) (https://doi.org/10.1080/0972060x.2021.1942231) ## Frequently asked questions ### Does citronella really repel mosquitoes? Citronella has documented repellent activity and is a popular natural option, but its effect wears off faster than synthetic repellents, so it needs frequent reapplication. It's a deterrent, not a guaranteed shield. ### Is citronella the same as lemongrass? They're related grasses but different oils. Citronella is citronellal/geraniol-rich; lemongrass is citral-rich. Both smell lemony, but their chemistry and uses differ. ### Is citronella phototoxic? No — citronella isn't phototoxic. Dilute it for skin because of its allergen content, but there's no sun-exposure restriction. ## Sources (GC-MS studies) - Romero AK, Portillo DJ, Beltrán SB, Sierra LJ, Álvarez CA, Ramírez KJ, Martínez JR, Stashenko EE. Enhanced Two-Step Extraction from Biomass of Two Cymbopogon Species Cultivated in Santander, Colombia. _Molecules (Basel, Switzerland)_, 2023. https://europepmc.org/article/PMC/PMC10488661 - Oliveira GDS, McManus C, Delgado F, Domingues J, Oliveira Filho JG, Salgado CB, Sousa HAF, Dos Santos VM. A New Antibacterial Protocol Based on <i>Cymbopogon nardus</i> (L.) Rendle Essential Oil and UV-C Radiation with Potential Application for Hatching Eggs. _Antibiotics (Basel, Switzerland)_, 2026. https://europepmc.org/article/PMC/PMC13510179 - Marzochi GR, Semensato LO, de Oliveira FS, Silva VCP, Fabri EG, Schinor EH, Hirata ACS, Forim MR, Kauffmann AC, Monquero PA. Essential oils as bioherbicides: effects of orange and citronella oils on weed germination and early growth. _Pest management science_, 2026. https://europepmc.org/article/PMC/PMC13569106 - Sereia MOP, Santos EAD, Leite LP, Neves RC, Marin VR, Ferreira H, Contiero J, Sass DC. Synergistic Effect of Essential Oils and Rhamnolipid on <i>Xanthomonas citri</i> Subsp. <i>citri</i>. _Microorganisms_, 2025. https://europepmc.org/article/PMC/PMC12114190 - Martínez-Téllez MÁ, Virgen-Ortíz JJ, Hurtado-Macias A, Talamantes-Soto RP, Hernández-Cristobal O, Peralta E, Zavala-Aranda SD, Colín-Chávez C. Sustainable PLA-Citronella Essential Oil Films: Development and In Vitro Antifungal Evaluation for Potential Blueberry Packaging Applications. _Foods (Basel, Switzerland)_, 2026. https://europepmc.org/article/PMC/PMC12985212 - EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP), Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M, Ramos F, Villa RE, Woutersen R, Chesson A, Schlatter J, Westendorf J, Dirven Y, Manini P, Dusemund B. Safety and efficacy of a feed additive consisting of an essential oil derived from the leaves of Cymbopogon nardus (L.) Rendle (citronella oil) for use in all animal species (FEFANA asbl). _EFSA journal. European Food Safety Authority_, 2024. https://europepmc.org/article/PMC/PMC11112456 - Uopasai S, Senaphan K, Borlace GN, Thongkham E, Aiemsaard J. In vivo mosquito repellency effect of citronella (Cymbopogon nardus (L.) Rendle) essential oil bath bomb formulation in dogs. _Veterinary world_, 2024. https://europepmc.org/article/PMC/PMC11344100 - Caballero-Gallardo K, Scudeler EL, Carvalho Dos Santos D, Stashenko EE, Olivero-Verbel J. Deleterious Effects of Cymbopogon nardus (L.) Essential Oil on Life Cycle and Midgut of the Natural Predator Ceraeochrysa claveri (Navás, 1911) (Neuroptera: Chrysopidae). _Insects_, 2023. https://europepmc.org/article/PMC/PMC10146085 - Santos C, Ramos A, Luís Â, Amaral ME. Production and Characterization of k-Carrageenan Films Incorporating Cymbopogon winterianus Essential Oil as New Food Packaging Materials. _Foods (Basel, Switzerland)_, 2023. https://europepmc.org/article/PMC/PMC10252829 - Champakaew D, Rattanasophon P, Phannasee C, Saehao W, Sukkanon C, Intirach J, Junkum A, Pitasawat B. Repellent effect of local indigenous knowledge-based repellent in Nakhon Si Thammarat, Thailand, against Aedes aegypti mosquito. _Heliyon_, 2023. https://europepmc.org/article/PMC/PMC10651505 - Pereira PS, Oliveira CVB, Maia AJ, Vega-Gomez MC, Rolón M, Coronel C, Duarte AE, Coutinho HDM, Siyadatpanah A, Norouzi R, Sadati SJA, Wilairatana P, Silva TG. Evaluation of the In Vitro Antiparasitic Effect of the Essential Oil of Cymbopogon winterianus and Its Chemical Composition Analysis. _Molecules (Basel, Switzerland)_, 2022. https://europepmc.org/article/PMC/PMC9099579 - Somala N, Laosinwattana C, Teerarak M. Formulation process, physical stability and herbicidal activities of Cymbopogon nardus essential oil-based nanoemulsion. _Scientific reports_, 2022. https://europepmc.org/article/PMC/PMC9206648 - Gaspar de Toledo L, Dos Santos Ramos MA, Bento da Silva P, Rodero CF, de Sá Gomes V, Noronha da Silva A, Pavan FR, da Silva IC, Bombarda Oda F, Flumignan DL, Gonzaga Dos Santos A, Chorilli M, Gottardo de Almeida MT, Bauab TM. Improved in vitro and in vivo Anti-Candida albicans Activity of Cymbopogon nardus Essential Oil by Its Incorporation into a Microemulsion System. _International journal of nanomedicine_, 2020. https://europepmc.org/article/PMC/PMC7778679 _Educational reference only — not medical advice. Essential oils are not intended to diagnose, treat, cure or prevent any disease._