French marigolds blossom in shades of yellow and orange and range between 5 and 18 inches in size. The marigolds are typically planted in window boxes or flowerbeds---and the blooms last longer than most marigold varieties. The French marigold flowers in the early summer until the first frost of the year. Useful for vegetable gardens, the scent of the French marigold repels insects.
Select a location where the French marigolds will receive full sunlight in the mornings. The marigolds will benefit from partial shade in the afternoon.
Loosen the soil in the spring once the threat of frost passes. Amend the composted soil with a rake. Remove rocks and weeds from the area, and add a 2-inch layer of peat moss to help improve the soil drainage.
Dig a hole with a shovel two times larger than the French marigold root ball. Make the hole as deep as the nursery container, and space each marigold 10 inches apart. Fill with soil and tamp down around the plants.
Water the marigolds to moisten the soil. The water needs to remain moist, so water the French marigolds when the top inch feels dry. The marigolds will need water more often in warmer climates, but do not over water the soil.
Apply a liquid slow-release fertiliser to the French marigolds after you plant them. Fertilise the flowers again in the summer. Follow the fertiliser application instructions before you apply it to the marigolds.
Remove spent flower blooms throughout the growing season. This will encourage new marigold blooms to form.