Marigolds are among the most popular and versatile annual flowers you can grow in your garden.
They come in various sizes, shapes, and colors, from the tall and majestic African marigolds to the petite and delicate signet marigolds.
They also have many benefits, such as attracting pollinators, repelling pests, and adding beauty to the landscape.
In this article, you will discover how to plant, grow, and care for marigolds, as well as how to handle some of the challenges they may face.
- What Are Marigolds?
- Growing and Caring for Marigolds
- How Tall Do Marigolds Get?
- What Problems Do Marigolds Face?
What Are Marigolds?
Marigolds are annual flowers that belong to the aster family, which also include daisies, sunflowers, and chrysanthemums.
They have daisy- or carnation-like flowerheads produced singly or in clusters.
The flowers can be yellow, orange, red, white, gold, or bicolor and usually bloom from summer to fall.
Marigolds are native to Mexico and Central America and have been cultivated for centuries for their medicinal, culinary, and ornamental uses.
There are three main types of marigolds:
- African marigolds (Tagetes erecta) are the tallest and most upright, reaching 3 to 4 feet (90-120 cm) tall and producing large, full flowers. They are also called American or Mexican marigolds.
- French marigolds (Tagetes patula) are smaller, bushier, and more compact, growing from 6 inches (15 cm) to 2 feet (60 cm) tall and having smaller flowers. They are also more tolerant of wet conditions than the other types.
- Signet marigolds (Tagetes tenuifolia) are petite and delicate, rarely reaching more than a foot in height and having tiny single-petal flowers. They are also called gem marigolds.
Calendula is a different plant, sometimes called pot marigold or English marigold. It has edible flowers with a tangy flavor that can be used in salads, soups, or teas. Calendula is not a true marigold and belongs to a different genus.
Growing and Caring for Marigolds
Marigolds are not very demanding, but they need some basic care to thrive and bloom well.
Here are some tips on how to grow and care for marigolds.
Choose the Right Location
Marigolds love sunlight, so plant them in an area that receives full sun for at least 6 hours a day.
Avoid planting them in shady or moist areas, as they are prone to powdery mildew and won’t flower well.
Prepare the Soil
Marigolds prefer well-draining soil that’s rich in organic matter.
They can grow in almost any soil but do best in moderately fertile and slightly acidic to neutral soil (pH 6.0 to 7.0).
Prepare the soil by digging down about 6 inches (15 cm) to loosen it, then mix in compost to add fertility and improve consistency.
Plant the Seeds or Transplants
You can start marigolds from seeds or buy them as seedlings (plug plants) or garden-ready plants.
If you start from seeds, sow them indoors 6 to 8 weeks before the last frost or outdoors after the soil can be worked.
Cover the seeds lightly with soil and keep them moist until they germinate.
Thin the seedlings to 8 to 18 inches (20-46 cm) apart, depending on the type of marigold.
If you buy transplants, plant them after the last frost at the same depth as in their pots.
Water and Mulch
Marigolds are drought-tolerant plants, but they appreciate regular watering during dry spells.
Water them deeply and let the soil dry out slightly between waterings.
Avoid overwatering or watering the foliage, which can cause root rot or fungal diseases.
Mulch around the plants with organic matter to conserve moisture and suppress weeds.
Marigolds do not need a lot of fertilizer, as this can reduce their flowering and make them more susceptible to pests.
If you grow them in pots, you can apply a balanced liquid fertilizer once a month during the growing season.
If you grow them in the ground, you can add some compost or slow-release fertilizer at planting time.
To keep your marigolds blooming throughout the summer and fall, deadhead them regularly by removing spent flowers.
This will prevent them from setting seeds and encourage more buds to form.
Specific Instructions for Each Type of Marigold
Here are some detailed instructions for different types of marigolds:
- African marigolds need more space between plants (12 to 18 inches, 30-46 cm) and may need staking to support their tall stems; they are drought-tolerant but appreciate regular watering during dry spells.
- French marigolds can be planted closer together (6 to 9 inches, 15-23 cm) and do not need staking; they are more tolerant of wet conditions but do not like soggy soil; they can be pinched back to encourage bushiness.
- Signet marigolds can be planted even closer together (4 to 6 inches, 10-15 cm) and make excellent edging or container plants; they are drought-tolerant but benefit from occasional watering; they do not need pinching or pruning.
How Tall Do Marigolds Get?
Marigolds can vary in height depending on the type and variety.
Generally, African marigolds are the tallest (3 to 4 feet, 90-120 cm), followed by French marigolds (6 inches to 2 feet, 15-60 cm) and signet marigolds (up to 1 foot, 30 cm).
The height of marigolds can also be influenced by factors such as growing conditions, pruning, and fertilizing.
For example, marigolds may grow taller in shady or moist areas or if they are over-fertilized.
If you want to control the height of your marigolds, you can try some of these tips:
- Choose dwarf or compact varieties that have shorter stems and smaller flowers.
- Plant them in full sun and well-drained soil to prevent legginess and rot.
- Pinch back the tips of young plants to encourage branching and bushiness.
- Avoid over-fertilizing or use a low-nitrogen fertilizer to limit growth and promote flowering.
What Problems Do Marigolds Face?
Marigolds are generally low-maintenance and pest-free plants but can still encounter some issues.
Here are some common problems that may affect marigolds and how to solve them.
This fungal disease causes a white or gray powdery coating on the leaves and stems of marigolds.
It usually occurs in humid or moist conditions, especially if the plants are crowded or watered overhead.
To prevent or treat powdery mildew, improve air circulation around the plants, water at the base of the plants, remove infected parts, and apply a fungicide if necessary.
This is another fungal disease that affects the roots and stems of marigolds. It causes the plants to wilt, yellow, and die.
It usually occurs in wet or poorly drained soil, especially if the plants are overwatered.
To prevent or treat root rot, improve drainage by adding organic matter or raising beds, water moderately and deeply, remove infected plants, and rotate crops.
Aphids are small black or green insects that suck the sap from the leaves and stems of marigolds.
They can cause stunted or distorted growth, black mold, and transmit viruses.
To prevent or treat aphid infestations, spray with water or insecticidal soap, introduce beneficial insects like ladybugs or lacewings, prune infested parts, and apply neem oil if necessary.
Slugs and Snails
These are slimy mollusks that chew on the leaves and flowers of marigolds.
They can cause holes, ragged edges, or missing parts on the plants.
To prevent or treat slug and snail damage, handpick them at night or use traps with beer or yeast, sprinkle diatomaceous earth or crushed eggshells around the plants, and use copper barriers or slug baits if necessary.
Marigolds are cheerful and easy-to-grow annual flowers that come in different types, sizes, and colors.
They need full sun, well-drained soil, and regular deadheading to thrive.
They can face some problems, but they are usually manageable.
Follow the simple steps in this article, and you will enjoy the beauty and benefits of marigolds in your garden or patio.