|Sonia Uyterhoeven is Gardener for Public Education. Join her each weekend for home gardening demonstrations on a variety of topics in the Home Gardening Center.|
The power of marigolds extend far beyond their color. Companion planting gurus extol the virtues of marigolds, claiming that they deter aphids, thrips, whiteflies, Mexican bean beetles, squash bugs, and tomato hornworms. With this kind of a reputation, what respectable vegetable gardener would go without them?
Some marigolds are supposed to deter nematodes that can attack tomato plants. This particular type of nematode tends to strike in sandy soils and is more prevalent in California, Florida, and the Gulf Coast region. If you see a marigold named ‘Nema-gone’ you know what it is advertising. Apparently, ‘Jolly Jester’ works, too.
The common name “marigold” applies to two genera: Tagetes and Calendula. The former (Tagetes) is the marigold that we are all familiar with. These marigolds are indigenous to the southwestern United States, Mexico, and into Central and South America and are generally broken down into four or five types.