Cheerful and bright, marigolds make an easy-to-grow addition to any garden plan—in pots or planting beds. These perky annuals bring terrific color all season long. What you might not know is that marigolds pack a punch to many insects, including mosquitoes, thanks to chemical insecticides they release. That’s why marigolds have such a strong odor when you touch them. Both flowers and leaves release the chemicals, but blossoms deliver the strongest punch. Other insects that marigolds deter include aphid, whitefly, thrips, tomato hornworm, Mexican bean beetle and squash bug. Tuck marigolds into pots on the patio to make summer evenings less buggy. Or use them in the vegetable garden to help repel pests.