Tagetes or French Marigolds are hardy and no-fuss annuals, easy to grow and rewards generously with non-stop flowering. With splashes of bright colours, they bloom non-stop throughout the growing season.
'Naughty Marietta' has lovely, rich golden yellow single flowers with maroon blotches and deeply divided aromatic leaves. They are one of the most effective bedders available. Use them at the front of the border or edge of a path. They are ideal for container gardening, with pots at porches, decks or window boxes. Marigolds are one of the mainstays of summer bedding schemes, performing well whatever the weather. The bright yellow blooms streaked with mahogany make Naughty Marietta ideal for massed plantings. Provide a sunny location and this fast growing plant will flower all summer long.
The edible flowers taste of orange or lemon. Use in sandwiches, salads, seafood chowders and hot desserts.
The plant is famously used in companion planting with many vegetable crops to repel harmful insects. The growing plant repels whitefly and can be grown near tomatoes to keep the crop free of the insect.
Secretions from the roots of the plants have an insecticidal effect on the soil, with a broad spectrum of activity. it is effective against many species of nematodes. For this reason it is used commercially as a form of green manure.
The secretions are produced about 3 to 4 months after sowing. It is very effective when used prior to planting strawberries and roses and with tuberous crops such as potatoes.
The whole plant contains substances that are toxic to cockroaches and to some extent against, slugs. Many “critters” (mice and other rodents) don't like them either, which make them excellent outside the confines of the garden fencing and as "perimeter protection" for individual beds in the garden.
Highly attractive to bees and butterflies, the varieties that have single flowers are a better choice for the gardener interested in wildlife: double varieties are less attractive to insects as they offer less pollen and nectar, which is often held in difficult to reach places.
Sowing: Sow in spring from early February to the end of May
Sow in a propagator at room-temperature from mid February to mid April. Sow under cold glass in a cold greenhouse or coldframe from mid March to the end of April. Or sow seeds directly outdoors two weeks before the last frost in April to the end of May. Stick the seed vertically into the compost.
Germination usually takes 5 to 14 days. Tagetes seeds germinate quite fast when exposed to humidity, after which the plant develops more slowly.
Use pots or trays of moist seed compost and cover with a very fine sprinkling of compost. The optimum growing temperature is around 21°C (70°F). After sowing, keep the surface of the compost moist but not waterlogged. When large enough to handle, transplant seedlings into 7.5cm (3in) pots to grow on. Harden off and plant out in full sun, after all risk of frosts (normally mid to end of May).
Sow thinly, 6mm (1/4in) deep in drills 30cm (12in) apart in well-cultivated soil which has been raked to a fine tilth. Water ground regularly, especially in dry periods. When large enough to handle, thin out until they are finally 15 to 22cm (6 to 9in) apart.
Keeping the plants well dead-headed makes them practically perennial!
Plants in full soil will benefit from a foliar feed every 2 weeks. Plants in baskets and containers require a fertiliser each week. Use a feed with balanced N and P (e.g. NPK 15-15-15). Don't apply fertilisers which contain ammonium when temperature has dropped below 17°C.
A yellow dye is obtained from the flowers of Tagetes patula. It is used to colour foods and textiles. The flowers contain lutein, a carotenoid pigment that can is extracted and used as a natural food colorant for livestock and pet food.
The flowers are sometimes used as an adulterant of saffron (obtained from Crocus sativus).
In the Indian subcontinent, the locally cultivated flowers of the French marigold are distilled for its essential oil. The oil is one of the most ancient perfume ingredients; it is often blended with sandalwood oil to produce 'Attar Genda' perfume. ‘Attar’ is a Persian word meaning fragrance, or essence, and is used to describe both the manufacture and application of oils. ‘Genda’ (or Gendha) is the name for the Marigold Flower.
The oil has antifungal properties and is also used to treat wounds, parasites and other ailments. It is currently being investigated for the treatment of fungal infections in plants.
Attar was first produced by the great Persian physician Hakim Ibn Sena (Avicenna in English). He was regarded as the greatest physician of his times, and used these for medicinal purposes. Attars include some individual essential oils, suitable for fragrance such as sandalwood, amber and patchouli. Sandalwood is both - an attar (used for its smell) and an essential oil. Attars can be blends of multiple oils, sometimes as many as 30 or 40 are blended together (a secret that many Attar-making families hold dear).
In South Asia, Tagetes is used to make garlands and curtains that help to purify the air. When worn, its purifying effect can be felt in the lungs and sinuses, people find themselves taking long, deep breaths without effort.
The colourfully bright yellow, orange and red flowers are used by the thousands as garlands and to decorate religious icons and festoon temples, people then meditate in the fragrant atmosphere. The blossoms are used as flower offerings in many Hindu ceremonies The plant is kept at the doors as a guard from mosquitoes and flies.
Marigolds are cultivated commercially as flower crops (floriculture) and cash crops in India and Pakistan. They are also grown worldwide in South Africa, Argentina, Egypt and France.
In the Mexican Dia de los Muertos celebration, also known as All Saints’ Day (November 1st), marigolds are a traditional flower laid out in abundance as offerings on the numerous altars that commemorate the lives of those who have passed from this realm.
In Chinese traditional medicine the flowers of Tagetes is used to cure colds, coughs and ailments. In the African continent, Tagetes erecta, The African Marigold, is similarly used to combat diseases and is one of the most used items to control and guard from pests and bugs.
This herbaceous ornamental annual plant, though native to Mexico and Central America, has been naturalised in many other warmer regions worldwide. Tagetes erecta were the first marigolds that were introduced into Europe and India in the 16th century from Northern Africa, hence the common name African Marigold. Since then, hundreds of cultivars have been created.
The genus name Tagetes is derived from that of the mythical Etruscan deity, Tages who supposedly emerged from the earth as it was being ploughed and was imbued with the power of divination.
The species name patula, is taken from the latin patulus meaning ‘spreading’ (to spread out or open wide) and is a reference to the way the flowers open wide.
In Spain, the flowers were the favourites to be placed on the altar of the Virgin Mary. Eventually they became known as Mary’s Gold and hence the common name marigold. In India, the plants grew to have religious significance and became known as the Friendship Flower.
- French marigold is the common name for Tagetes patula. They are small bushy plants that about 15 to 30 cm in height. The flowers are up to 5 cm across and are composed of a dense arrangement of “rays” that come in yellow, orange and a unique bronze color. The French marigolds bloom continuously until cut down by frost. Though doubles are available, singles or semi-doubles are more common. The single flowering forms stand-up to rain and humidity better in the south than double forms.
- African (or American) marigolds is the common name for Tagetes erecta - tall stout plants that grow to 90cm (36in) in height. They have larger blossoms and a shorter flowering period than French marigolds (often with fewer, larger double flowers). In the double flowering forms, there are crested doubles where the flowers appear mounded and full, and anemone doubles where the flowers appear flat and wide with the centre recessed.
- Triploid marigolds (Signet hybrids) are sterile hybrids (seed won't germinate) obtained by crossing the French with the African species. These triploids are non-stop bloomers with impressive 8 cm flower heads in clear warm colours of gold, yellow, red and russet.
Red and crimson are found in the triploids and French forms but not the African. Neither African or French marigolds come from Africa or France but both are native to Mexico.
T. erecta and T. patula are among the most common border plants in temperate gardens, There are two other species, T. tenuifolia and T. minuta that are slowly becoming more available.
Tagetes minuta, also known as the Mexican marigold is the most powerful of the insect repelling marigolds and is said to overwhelm weed roots such as bind weed.
Companion Planting and Green Manure.... the science bit !
Contrary to common knowledge Tagetes is not primarily used as an ornamental plant, but as a biological aggressor against root nematodes of the genus Pratylenchus. These nematodes do not invade the roots of its host but consumes it - this is called ectoparasitic behaviour (vs. endoparasitic nematodes which house inside the root).
Secondary damage can occur when these nematodes are accompanied by a fungus which can now freely invade the wounds. Certain Tagetes species grow endodermic cells which contain thiophenes - the molecule C4H4S which contains sulphur. When the roots of these species of marigold get damaged the plant starts manufacturing an enzyme called Peroxidase, which binds with the sulphur from thiophene. The result of this is ozone, which kills the nematodes.
Research has shown that a successful T. patula crop can suppress Pratylenchus penetrans for a few years in a row. In other words, one can plant marigolds among tuberous plants – potatoes, strawberries and roses to protect them and fight back against nematodes without using pesticides. This genus has become increasingly popular for that purpose due to increasingly stringent laws on soil sanitation and large-scale application of pesticides.
An effective nematode-fighting crop requires 3 to 5 months of Tagetes growth, preferably during the summer months. This will allow them to grow an impressive system of roots, nematodes which don't come into contact with the roots will not be killed. In the entire genus it is T. patula which is best used to fight nematodes and T. erecta is an alternative. T. minuta doesn't offer any active protection and is mostly used to produce organic mass.
Root nematodes are a problem associated with lighter/poorer soils, using marigolds in heavy soil is normally not done. Furthermore, heavy soils are more difficult to prepare: soil for sowing Tagetes needs to be easy to crumble as seeds are raked in to shallow depth.
Planting space is critical to erect a barrier against root nematodes, don't plant them more than 25cm (10in) apart. Since the plants develop slow in the first few months they can get overrun by weeds.
The crop can afterwards be worked into the soil to improve it, plants are very sensitive to frost and will die after the first serious freezing at night in autumn. This can be worked in immediately using a cultivator. One can also leave the crop on the field to protect against erosion from wind and rain. Tagetes has a root system which improves the structure of the soil.
- Additional Information
Packet Size 1 gram Average Seed Count 320 Seeds Family Asteraceae Genus Tagetes Species patula Cultivar Naughty Marietta Common Name French Marigold Hardiness Half Hardy Annual Flowers Golden yellow single flowers with maroon blotches Natural Flower Time From spring until first frosts Foliage Dark green, deeply divided leaves. Height 30cm (12in) Spacing 15 to 22cm (6 to 9) Position Full sun Aspect West or south facing. Exposed or sheltered. Time to Sow From Early February to the end of May Germination 5 to 14 days.