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Pelargonium citrosum
citronella geranium
Garden hybrid — a scented {Pelargonium} selection; the genus is native to South Africa
Overview
Pelargonium citrosum is the citronella geranium, growing 18–36 inches (45–90 cm) tall and 18–24 inches (45–60 cm) wide. Medium green deeply lobed leaves 2–4 inches (5–10 cm) release a citronella-lemon fragrance when touched, brushed, or crushed. Not a true geranium — in Pelargonium (family Geraniaceae), often marketed as 'mosquito plant' or 'citronella plant.' Studies on the repellent efficacy of the intact plant show that the aromatic compounds are not released into the air in sufficient concentration to repel mosquitoes when the plant is sitting undisturbed — the oils are bound in the leaf tissue and require physical crushing to release. Crushed leaf extract applied to skin has some repellent activity, though less than DEET-based products in comparative trials. Small pink-lavender flowers 0.5–0.75 inch (12–18 mm) sporadically. Frost-tender: killed by frost. Zones 9–11 outdoors; grown as a summer annual or container plant in cold zones. Full sun to partial shade. Containers of 2–5 gallons (8–20 liters). Well-draining soil — overwatering causes stem rot. Deer-resistant (the aromatic foliage). Non-toxic. Propagates easily from stem cuttings. Whitefly is the primary pest. The lemon-citronella fragrance releases on contact with the foliage.
Native Range
The genus Pelargonium is native to South Africa. 'Citrosum' is a scented hybrid.Suggested Uses
Grown in containers of 2–5 gallons (8–20 liters), borders, and along walkways where the foliage is brushed in passing. Full sun to partial shade. Frost-tender — bring indoors before frost in cold zones. Deer-resistant. Non-toxic.How to Identify
Appearance
Size & Dimensions
Height1'6" - 3'
Width/Spread1'6" - 2'
Reaches mature size in approximately 1 years
Colors
Bloom Information
Small pink-lavender flowers sporadically. The citronella-scented foliage is the year-round feature — fragrance releases on contact with leaves.
Detailed Descriptions
Flower Description
Lavender-pink, small, in clusters — secondary to the aromatic foliageFoliage Description
Medium green, deeply lobed, INTENSELY LEMON-CITRONELLA SCENTED when touched or brushed — the signature fragranceGrowing Conditions
Sun Requirements
Requires 4-8 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Full sun to partial shade. Well-draining soil — stem rot in wet conditions. Frost-tender — bring indoors before frost. Propagates from stem cuttings. Deer-resistant. Non-toxic. Whitefly. The aromatic oils require physical contact to release.Pruning
Pinch growing tips for bushier growth. Remove leggy or woody stems in spring. Propagate from 4–6 inch (10–15 cm) stem cuttings in spring or summer.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
early spring
Container Growing
Suitable for container growing
Minimum container size: 5 gallons