Marigold is a beautiful and versatile plant in the garden. Planted as soon as the ground warms up in spring, it brightens the garden with its yellow, gold and orange blooms until the first hard frost. As beautiful as it is, marigold has long been an excellent companion plant, solving many garden pest problems.
Many gardeners are looking for solutions to garden pest problems that are non-toxic and earth-friendly. Marigold is a long-established companion plant that does no harm to children and pets. It mitigates many garden problems without causing harm to the target plant or other plants. Marigold imparts no toxicity to food crops.
Marigold contains thiopene, a chemical toxic to many soil-borne pests. Thiopene gives marigold its distinctive odor and flavor, which makes it practically immune to garden pest problems.
Nematodes, a soil-borne parasite causing plant decline and death in many vegetable and ornamental plants are repelled by the thiopene that marigold emits into the soil through its roots.
Insects are repelled by the strong, chemical odor of marigold. Soft-bodied, sucking insects, like aphids, are particularly adverse to the chemical smell and flavor of marigold. Marigold is very effective against carrot root fly.
Deer hate the smell and flavor of marigold. Vegetables and ornamentals planted near marigolds are less likely to be eaten by deer.
Plant marigold in rows in the vegetable garden as a barrier to nematodes and other soil-borne parasites. Plant near tomatoes and root vegetables. Thiopene will penetrate the soil, making surrounding areas less susceptible. Marigolds planted near roses will help repel aphids, which associate marigold's smell with its unpalatable flavor.