Tagetes is a genus of annual or perennial, mostly herbaceous plants in the sunflower family Asteraceae. They are among several groups of plants known in English as marigolds.
Tagetes species vary in size from 0.1 to 2.2 m tall. Most species have pinnate green leaves. Blooms naturally occur in golden, orange, yellow, and white colours, often with maroon highlights. Floral heads are typically (1-) to 4–6 cm diameter, generally with both ray florets and disc florets. In horticulture, they tend to be planted as annuals, although the perennial species are gaining popularity. They have fibrous roots.
Tagetes species grow well in almost any sort of soil. Most horticultural selections grow best in soil with good drainage, and some cultivars are known to have good tolerance to drought.
Depending on the species, marigold foliage has a musky, pungent scent, though some varieties have been bred to be scentless. It is said to deter some common insect pests, as well as nematodes. Tagetes species often used in companion planting for tomato, eggplant, chili pepper, tobacco, and potato. Due to antibacterial thiophenes exuded by the roots, Tagetes should not be planted near any legume crop.
Marigold has been used as a source of essential oil for the perfume and industry known as tagette or “marigold oil”, and as a flavourant in the food and tobacco industries. It is commonly cultivated in South Africa, where the species is also a useful pioneer plant in the reclamation of disturbed land.
Marigolds are recorded as a food plant for some Lepidoptera caterpillars including the dot moth, and a nectar source for other butterflies and bumblebees. They are often part of butterfly gardening plantings. In the wild, many species are pollinated by beetles.