It is a cheerful flower bed plant and can also be an excellent addition to a vegetable garden. The French marigold, or Tagetes patula, had a similar journey. French Marigolds are small, fast growing, bushy plants that grow 12" tall and wide. French Marigolds will provide a non-stop show of dense, 1½"-2" Carnation-like double flowers in shades of yellow, orange or reddish-brown from early summer until late fall if the spent flowers are removed promptly. French marigolds are an easy to grow annual that will bloom brightly all summer long. Don’t crowd potted marigold plants, as healthy marigolds require plenty of air circulation. T. patula made its home in France and became a popular flower in the region, earning its common name. pot, but you can grow two or three in a 12-inch (30 cm.) Signet Marigolds – This is a marigold that has a single bloom that resembles that of a daisy. Caring for Marigolds in Pots. pot, and five or more small plants in a … French Marigolds – This is one of the most common types of marigolds. Their seeds crossed the ocean from the Americas with European explorers who were returning home. A garden favorite for their brightly-colored flowers, French marigolds are also easy to grow and care for. These heat-loving annuals last the entire growing season, blooming away until frost. One marigold is enough for a 6-inch (15 cm.) They grow to be about five to 18 inches in height, and they often have a double flower head that is yellow and orange. Along with their ornamental attributes, French marigolds are also edible and can be used to make a natural dye.