Imagine a flowering plant so beautiful and sturdy that it lends equal brightness to elegant flowerbeds, gas station plantings and public parks all over the United States. Leaping nimbly over national borders, it also serves as an important decorative element for festivities associated with the Mexican Day of the Dead and plays a prominent role in all kinds of celebrations on the Indian subcontinent. It repels deer and other varmints, but attracts humans, who use it as a summer garden stalwart, harvest it for indoor arrangements and sometimes even strew it over salads.
The plant in question is an annual with an interesting Latin name—Tagetes—and a familiar English one—marigold. Blooming in shades of cream, yellow, gold, orange/red, red or maroon, its cheerful disposition and easy-going nature match its sunshiny colors. Some of the most sophisticated gardeners in history, like early twentieth century designer/author Gertrude Jekyll, have taken marigolds to their hearts and into their landscapes. Yet, it has also edged humble vegetable plots, anchored cutting gardens and been used as a natural pest controller. Fragrant and sturdy, the annual marigold is a classic summer bloomer.
The two most popular species are the African marigold and the French marigold (Tagetes erecta). In keeping with the Latin name, the African erecta varieties are tall, growing between one and four feet. French varieties are shorter, maxing out at 18 inches. I am especially fond of the flashy French variety, ‘Harlequin’, an antique that features petals with alternating gold and mahogany strips. Both erecta marigolds sport pinnate or feathery leaves. Many popular marigold varieties are actually crosses between these two variants, combining the somewhat more compact habit of the French types, with the large flowers of the African marigolds. Though not as widely known, little Tagetes tenuifolia, commonly known as signet marigold, features petite, elegant, single blossoms and works well in containers and edging situations. The single-flowered varieties ‘Tangerine Gem’, ‘Lemon Gem’, and ‘Paprika’ are perfect examples.
In addition to their many other virtues, marigolds are good travelers. Early Spanish colonists took the plants from their native Mexico, where they were sacred to the Aztec goddess Xochiquetzal, back to the Old World, where they flourished. Their popularity spread quickly to all kinds of places, including France and North Africa. This migration gave rise to the idea that the plants were native to those areas, hence the common names of some species.
Daisies are the show-horse flowers of summer and marigolds are in the daisy family, Asteraceae. As with other daisies, each flowerhead is actually a mass of tiny flowers. The “eye” features a disk of tiny flowers surrounded by the showy, petal-like ray flowers. The red and gold ‘Scarlet Starlet’, with its golden eye and deep scarlet petals, is a perfect example. “Double-flowered” marigolds, like those of the tall, white-flowered ‘Snowdrift’, are not truly double but instead have only ray flowers. Given their origins in Mexico, it is not surprising that the plants still prefer sunny, open situations and grow best when it is very warm.
Marigolds are among the easiest plants to grow—perfect for children and beginning gardeners. Most garden centers feature cell packs of starter plants in the spring and summer, but marigolds can easily be started from seed. Sow directly into pots or garden beds and cover with a thin layer of soil or Fafard® Seed Starter Potting Mix with RESiLIENCE®. Fafard® Ultra Potting Mix With Extended Feed and RESILIENCE® is a perfect medium for container-grown specimens.
Water daily and seedlings should appear within a week or so. Thin the young plants to prevent crowding and once they have leafed out, pinch back the stems to promote bushy growth and abundant flowers. Established marigolds are somewhat drought tolerant, though container-grown specimens may need extra water during dry spells.
Gardeners tend to either love or hate the strong smell of marigolds’ flowers and foliage, which have earned the plant the old-fashioned nickname, “Stinking Roger”. However, even those who hate the aroma can love the fact that marigolds have the ability to beat back the destructive power of root-knot nematodes, organisms that can damage or destroy the roots of tomatoes and other food crops. Marigolds’ roots secrete a substance called alpha-terthienyl that inhibits the growth of these parasitic nematodes. To use marigolds in this way, it is best to sow them as a cover crop between planting seasons. This inhibiting power, traditionally harnessed in countries like India, may account for the fact that farmers in many places have traditionally planted marigolds around vegetable beds. If nothing else, they brighten up kitchen garden planting schemes.
Marigolds are a study in contrasts. Their simple flowers have enchanted sophisticated gardeners all over the world, while their down-home demeanor successfully masks a deadly arsenal of anti-nematode weapons. They are at once the stealthiest and most alluring denizens of the summer garden.