Insecticidal plants emit chemical compounds that naturally deter common pests. This trait alone makes them our best friends around decks and patios, let alone how pretty they are. These genetic traits have been developed over thousands of generations. In some cases, they have become very specific, in others it is more generic.
The insecticidal tendencies of certain plants is the basics of using essential oils in the garden. In some cases the plants root interaction with the soil and soil dwelling organisms have the greatest insecticidal benefit. They have a more beneficial impact when directly planted in the soil. This is especially true in a low maintenance garden. By planting perennial plants that have insecticidal traits, their effects are felt season after season, without too much further input from us.
Cabbage looper, Carrot fly, Slugs
Aphids, Squash bugs, Cabbage looper
Cabbage looper, Root maggot, Corn earworm, Tomato hornworm, Whitefly
Ants, Cabbage looper, Cabbage maggot, Flea beetle, Carrot fly, Codling moth, Mice
Whitefly, Cabbage moth, Aphids, Squash bug
Whitefly, Root-feeding nematodes
Carrot fly, Cabbage worm, Slugs, Tomato hornworm, Aphids
Carrot fly, Aphids
Tomato hornworm, Cabbage looper
Squash bugs, Cabbage looper