Exploring Lantana Camara: A Tropical Gem for Gardens

Lantana camara, a plant species from the Verbenaceae family, originates from the tropical regions of America. It is a dual-purpose ornamental plant and an excellent shrub species for protecting embankments, slopes, and dikes.

The leaves and unripe fruit of Lantana camara are toxic, and if ingested by humans or livestock, can lead to poisoning.

I. Basic Introduction

Lantana camara, a plant species from the Verbenaceae family, is an upright or trailing shrub, growing 1-2 meters high, sometimes vine-like, extending up to 4 meters. Both stems and branches are quadrangular.

The leaves are opposite and when crushed, emit a strong odor. The leaf blades are ovate to oblong-ovate. The inflorescence has a diameter of 1.5-2.5 cm.

The inflorescence stalk is robust, longer than the petiole, and the bracts are lanceolate, 1-3 times as long as the calyx, with coarse hair on the outside. The fruit is spherical, about 4mm in diameter, and turns purple-black upon ripening. It flowers all year round.

Originally from the tropical regions of America, it can be found in tropical regions worldwide. It often grows on coastal beaches and open areas at altitudes of 80-1500 meters.

The roots, leaves, and flowers of Lantana camara can be used for medicinal purposes, having heat-clearing, detoxifying, and analgesic effects.

It is a dual-purpose ornamental plant and also an excellent shrub species for greening, barren hills, grasslands, stony mills, gullies, and slopes, particularly for protecting embankments, slopes, and dikes.

Industrially, the roots of Lantana camara contain rubber-like substances that can be used to manufacture rubber, and the stems are raw materials for papermaking. The leaves can be added to tobacco to enhance the flavor and can also replace sandpaper for polishing.

The leaves have insecticidal properties and can be used to manufacture biological insecticides. However, the leaves and unripe fruit of Lantana camara are toxic, and if ingested by humans or livestock, can lead to poisoning.

II. Growth and Distribution

Growing Environment

Lantana camara often grows on coastal beaches and open areas at altitudes of 80-1500 meters. It prefers warm, moist, sun-facing locations, is drought-tolerant, slightly shade-tolerant, but not frost-tolerant.

It has low soil requirements, but fertile, loose sandy soil is optimal. It is hardy and can grow all year round in tropical areas, without going dormant in winter.

Distribution Range

Originally from the tropical regions of America, it can be found in tropical regions worldwide.

III. Characteristics and Features

This is an erect or creeping shrub, standing at 1-2 meters in height. Sometimes it’s vine-like, reaching up to 4 meters. Both the stem and branches are quadrangular, covered with short pubescence and usually equipped with short, recurved thorns.

The leaves are single and opposite, emitting a strong odor when crumpled. The leaf blade is ovate to oblong-ovate, measuring 3-8.5 cm long and 1.5-5 cm wide. The leaf tip is acute or acuminate, with a heart-shaped or cuneate base.

The leaf margin is blunt-toothed; the surface is rough with wrinkles and short pubescence, and the back is covered with small stiff hairs. The petiole is about 1 cm long.

The inflorescence is 1.5-2.5 cm in diameter. The peduncle is robust, longer than the petiole. The bracts are lanceolate, 1-3 times the length of the calyx, covered with coarse hairs.

The calyx is tubular and membranous, about 1.5 mm long, with extremely short teeth at the tip. The corolla is yellow or orange-yellow, turning deep red shortly after blooming.

The corolla tube is about 1 cm long, with fine short hairs on both sides and a diameter of 4-6 mm. The ovary is hairless. The fruit is spherical, about 4 mm in diameter, turning purple-black when mature. It blooms year-round.

IV. Cultivation Method

This plant is highly resistant and essentially free from pests and diseases. As it’s robust and grows quickly, the main focus in care is to prevent overgrowth or leggy growth. Therefore, during the peak growth season, regular pruning is necessary.

The principle is to prune heavily after flowering, especially when the branches and leaves become too dense or long (exceeding 40 cm above the ground), or when the flowers and leaves cover each other, exposing the stem.

Pruning should be done promptly. About 20-25 days after pruning is the best bloom time, making the ground cover plants reach the best viewing effect with a flat and even surface, and pure and bright flower color during the holiday season.

V. Propagation Method

Seeding: Seeds can be sown when the room temperature is 16-20℃ from March to April. The fastest germination occurs at 25-28℃, taking about 10-15 days.

The seeds are small and juicy, so they shouldn’t be sown too deep. They can bloom in the same year of sowing, but this method is less commonly used in production.

Cutting: The best cuttings are taken in spring from tender branches, which have a high survival rate. In other seasons, choose semi-woody branches that are about 5 cm long with nodes.

They generally root in 20-30 days. Once they grow to 7-8 cm, they can be planted out. After successful planting, they form buds and bloom continuously.

VI. Disease and Pest Control

Species Hazard

The Lantana camara is categorized as a level II invasive plant species, and is also regarded as one of the ten most harmful weeds in the world.

The Lantana camara has a strong allelopathic effect. Its volatile oils, phenolic acids, and flavonoids not only inhibit the growth of some weeds, but also noticeably suppress the surrounding plants.

This makes it a malignant weed that invades pastures, forests, tea plantations, and orange groves, severely damaging forest resources and ecological systems once it has invaded.

As an invasive species, the biosecurity of the Lantana camara is yet to be researched. If introduced and cultivated blindly, the potential ecological risks it may cause must be taken seriously.

The Lantana camara is extremely hardy and adaptable. Its seeds can be quickly spread by birds, monkeys, and sheep, either through air drop or defecation. At the same time, its entire plant or remains can produce strong plant-inhibiting or allelopathic substances.

Therefore, Lantana camara has become a malignant “weed” that invades pastures, forests, tea plantations, and orange groves, severely damaging forest resources and ecological systems.

The Lantana camara also provides a hiding place for rodents, wild boars, and harmful insects like the tsetse fly in farms, pastures, and forests.

Control Measures

Chemical control can use herbicides, and biological control can utilize natural enemies. It can also be uprooted when the soil is soft during the rainy season.

However, each method has its drawbacks, such as residual toxicity from chemical herbicides that can cause environmental pollution. Therefore, integrated measures should be adopted, including mechanical, cultivation, chemical, and biological methods.

Plant Toxicity

The entire plant and roots of the Lantana camara are poisonous. The toxic components mainly include triterpenic acids such as lantadene acid, norlantadene acid, lantadenes A and B, and lantadene alkaloids.

Livestock such as cattle, horses, sheep, and dogs, as well as humans, can be poisoned if they consume its leaves. Cases have been reported in Australia, India, New Zealand, South Africa, and the Americas.

Symptoms and signs of poisoning include: constipation, loss of appetite, acute abdominal pain, photosensitivity, dermatitis, cheek, tongue and gum ulcers, corneal opacity, gallbladder paralysis, bile duct obstruction and bile stasis, jaundice, liver and kidney failure, hematuria, intestinal bleeding, vomiting blood, and myocardial damage.

Animals weighing 181 kg have been found to die from poisoning within 1 to 4 days of consuming approximately 400 grams of Lantana camara leaves. The survival rate of poisoned livestock is extremely low, and the survivors are not worth continuing to raise.

VII. Value and Other Aspects

Primary Value

Medicinal Use

The root, leaves, and flowers of this plant can be used for medicinal purposes. They have detoxifying, heat-clearing, pain-relieving, and itch-soothing properties.

It can be used to treat symptoms of high fever from colds, chronic fever, dysentery, tuberculosis, bronchial asthma, hypertension, and more. A decoction of the stems and leaves can be used to treat eczema, scabies, toxic sores, dermatitis, and skin itching.

The plant can also be used to reduce swelling and treat sprains and bruises when mashed and applied to the affected area.

Ornamental Use

This plant is an ornamental plant valued for its leaves and flowers. It has a long flowering period and can bloom all year round, with the best period being from late spring to autumn.

The flowers are small, but when they gather together, they look like colorful little pom-poms nestled or dotted among the green leaves.

The color of the flowers is beautiful and varied, with each flower changing through many colors from the bud stage to the wilting stage, thus it is also known as the five-color plum or the seven-variable flower.

There are also many cultivated varieties, including those with golden yellow, orange-red, pink, and milky yellow flower crowns.

The plant can be grown en masse in streets, gardens, courtyards, flower beds, by walls, roadsides, vegetable fields, and orchards as hedges, or individually in pots as elegant potted plants for decoration and beautification of halls, meeting rooms, rooms, flower beds, rockeries, stone crevices, corners of houses, courtyards, and other environments.

Ecological Aspects

This plant has strong reproductive capacity, fast growth, wide adaptability, no particular soil preference, high temperature tolerance, drought resistance, few pests and diseases, a well-developed root system, strong stem and branch sprouting, and a large canopy coverage.

It can grow alone or in groups and can coexist with other trees, shrubs, and herbaceous plants. It is effective in reducing wind and rain erosion of the ground, conserving soil and water, improving soil, increasing fertility, and improving the ecological environment.

Therefore, it is an excellent shrub species for greening, barren hills, grasslands, rocky areas, gullies, slopes, and especially for protecting banks, slopes, and embankments.

Economic Aspects

In industry, the root of the plant contains rubber-like substances that can be used to produce rubber, and the stem is a raw material for papermaking. The leaves can be added to tobacco to enhance the flavor and can also substitute for sandpaper for polishing.

Although the essential oil extracted from the bark, leaves, and flowers of the plant is in small amounts (0.15%), it resembles peppermint oil, has a good fragrance, and has activity similar to juvenile hormones.

The allelopathic substances released from the seeds and the whole plant, particularly the leaves, can be used to make biological herbicides. The leaves have an insecticidal effect and can be used to make biological pesticides.