From The Telegraph
August 6, 2019
If mosquitoes, gnats, black flies and no-see-ums are driving you buggy, then consider cozying up to some lavender, marigolds or basil. Scientists question their overall effectiveness, but many fragrant ornamental flowers and herbs grown around the home have properties that can repel insects.
Insect repellents are divided into two primary chemical classes: natural and synthetic. How effective they are depends on the targeted insects and the host plants’ essential oils.
“Plant-derived insect repellents are very volatile compounds that work but exhaust themselves very quickly,” said Walter Leal, a biochemist and distinguished professor at the University of California, Davis. “They’re good, but they should last for a longer time.”