Geraniums contain mosquito-repellent geraniol. Florist geraniums have the greatest geraniol. Geraniums aren't cold hardy but can be grown outdoors in summer. They like sunshine.
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Citronella Geraniums aren't citronella. Both are efficient insect repellents, although their oils differ. Geranium has more citronellol than grass. In insect-repelling candles and torches.
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Lemongrass has mosquito-repelling citral and geraniol. "Natural" mosquito repellents contain citronellol, limonene, and linalool. In damp climates, lemongrass thrives. Divvy up large clumps. Some areas overwinter well.
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Contains rosmarinic acid, citronellol, and geraniol. Rosemary is acidic. Lemon balm makes a delicious tea. Invasive if the black seeds spread into the lawn. My dog did it. Mowing near them releases their oils.
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Lavender contains mosquito-repellent pinene and linalool. These two compounds in lavender repel mosquitoes. In well-drained soil, lavender thrives. The leaves contain as much oil as the flowers in the first year.
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Marigolds prevent potato bugs, according to an old saying. It's tagetone and limonene.  Tagetone's presence in the garden repels mosquitoes. Marigolds are annuals with yellow and orange flowers.
In most places, Eucalyptus is ornamental, but in Australia and the Gulf Coast, it's a weed. In mild climates, winterize in a pot. Eucalyptus has mosquito-repelling pinene and limonene.
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Rosemary is used in cooking. It contains rosmarinic acid, pinene, and borneol, which repel mosquitoes.
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Lantana, an African native, has naturalised in the Everglades. The leaves' odour can help keep mosquitoes away. Two lantana compounds (lanatoside and lantanone) are being studied.
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