LOBELIA: CHARACTERISTICS, HABITAT, DISTRIBUTION, SPECIES - BIOLOGY - 2025

Lobelia is a genus belonging to the Campanulaceae family that groups approximately 437 species of herbs and shrubs. They are annual and perennial species, some with terrestrial habits and others with aquatic habits.

Lobelias are plants with woody stems at their base, flexible and thin. The leaves are light green in color with a strong aroma and sharp smell. The flowers of these plants are small and tubular, but they are present in great numbers.

Lobelia sp. Source: pixabay.com

Furthermore, the flowers are arranged in terminal racemes or on ears, although solitary flowers can be found. The color of the flowers varies according to the species or variety and you can find colors such as blue, purple, red or white.

These plants have certain properties due to substances they contain such as lobeline, which is used as a stimulant and relaxant. It is an easy genus to grow and very attractive in gardens.

characteristics

Habit

They are generally herbarium and shrub plants, annual or perennial. Herbs are sufrutic and shrubs latescent. The stem of these plants is woody at its base, while being flexible and thin.

Leaves

The leaves of the plants of this genus are simple, serrated with a tendency to sub-integers and the teeth callus. In addition, they have a strong aroma and a sharp smell. The light green color is characteristic of the leaves of this genus.

Inflorescence of Lobelia siphilitica. Source: pixabay.com

flowers

The flowers are tubular and have a calyx with five unequal teeth, the corolla is monopetal and irregular with a cylindrical tube longer than the calyx. The limbus is divided into five lanceolate parts.

Normally, the flowers are arranged in terminal clusters or in the axils of the upper leaves of the plant. The flowers are inverted, bibracteoladas and subject to a pedicel.

In turn, these flowers have striking colors that make them very attractive in gardens. These colors range from blue or purple flowers to red or white.

White flowers typical of lobelias. Source: pixabay.com

Taxonomy

-Kingdom: Plantae.

-Filo: Tracheophyta.

-Class: Equisetopsida.

-Subclass: Magnoliidae.

-Superorden: Asteranae.

-Order: Asterales.

-Family: Campanulaceae.

-Subfamily: Lobelloidae.

-Gender: Lobelia L. (1753).

Habitat and distribution

The genus Lobelia is distributed throughout the United States, Brazil, China, Colombia, Honduras, and Mexico.

It is found in tropical and subtropical regions at an altitude ranging from 0 to 4000 meters above sea level. The environment it occupies must be from humid to marshy, and some varieties can be cultivated in places where cold weather is predominant.

Properties

Plants of this genus have medicinal properties thanks to the chemical substances they contain. For example, some of the active alkaloids they contain are lobeline, lobelanidine, and norlobelanidine. Among them, lobeline is a carotid stimulant for humans.

One of the applications of this plant is that when it is added to cigarettes in very small quantities, it acts as a kind of euphoria similar to that caused by marijuana.

Lilac flowered lobelia in a garden Source: pixabay.com

Lobeline also acts both as a stimulant and a relaxant. In this sense, small amounts act as stimulants and larger amounts act as sedatives.

On the other hand, plants of the genus Lobelia are considered one of the best-acting herbal expectorants, as well as a powerful emetic.

Some species such as Lobelia inflata were used as tobacco at the beginning of the 19th century. However, its consumption in excess or in high doses can become toxic.

Main species

The genus Lobelia comprises approximately 437 species. Some of the representative species are: Lobelia cardinalis, Lobelia inflata, Lobelia eckloniana, Lobelia ionantha, Lobelia schmitzii, Lobelia chinensis, Lobelia clavata, Lobelia comosa, Lobelia darlingensis, Lobelia dodiana, Lobelia hybrida, Lobelia jaliscensis, Lobelia puberula, Lobelia laxerula erinus, Lobelia spicata, Lobelia siphilitica, among others.

Lobelia fenestralis

It is commonly known as foxtail, talclote, purple lobelia. It is part of the landscape of grasslands and edges of land or parcels with a striking inflorescence that looks like a tail.

It is a herbaceous plant about 15 to 70 cm tall, with alternate, sessile leaves. The flowers have a blue tube-shaped corolla with several perforations. The central root is woody.

Lobelia cardinalis

It is a plant that has bright red flowers, similar to the costumes of the cardinals of the Catholic Church. That is why the name of this species is due.

Lobelia cardinalis or Queen Victoria. Source. pixabay.com

Grumpy Lobelia

The Lobelia gruina is a 20-65 cm tall grass that is part of the vegetation along the roads and high areas. It is distributed in Mexico and the extreme south of the United States. It is commonly known as Flor de María.

It has alternate leaves with petioles, an erect stem with ascending green to purple branches towards its base. The flowers are blue or blue-purple and are 1.3 to 2.2 cm long. The flowers have 5 lobes at their upper end.

They have a dried fruit in the form of a capsule that opens through shells. The seeds are small, smooth and brown in color.

Lobelia inflata

It is commonly known as Indian tobacco, horse killer, or asthma herb. The flower of this plant is fragile and light blue-violet in color with a yellow part. It is about 80 cm tall and is a biennial plant.

It is distributed in southeastern Canada in Nova Scotia, to southeastern Ontario and British Columbia. It is also located in the United States.

It is a very toxic plant whose consumption can cause vomiting, hypotension, tachycardia, seizures and death from respiratory paralysis. Its use is recommended in an emergency to treat asthma, chronic bronchitis and respiratory failure.

Lobelia inflata contains lobeline which contains a chemical composition similar to nicotine. For this reason, the aborigines smoked the dried leaves of this plant, but for medicinal purposes.

The leaves, flowers and seeds of this plant are used. However, it is the seeds that produce the most potency due to the piperidine alkaloid.

Care

Lobelia plants are easy to grow, are treated like annuals, and are commercially available as ornamentals. These plants are generally not affected by major cultivation problems.

The optimal lighting conditions are those in a shaded or semi-shaded position. However, they require a certain amount of light, but in the cooler hours of the day.

Regarding the way of cultivation, these are usually in pots or directly in the ground, in which case they look beautiful as borders due to the varied color of their flowers.

Purple and pink lobelias in garden. Source: pixabay.com

Irrigation

Irrigation for these species must be carefully regulated, observing the evaporation of water from the soil surface between one irrigation and the next.

Floor

You should try to offer a good fertile mantle based on peat and sand. In this way, the soil is enriched while promoting good drainage.

Fertilization

From the spring and during the summer, a type of liquid fertilizer in medium concentrations or doses must be supplied together with the irrigation water.

The fertilizer used must contain nitrogen, phosphorus, potassium, in addition to microelements such as manganese, iron, copper, zinc, boron, magnesium, molybdenum, as all of them are necessary for the growth of these plants.

Pruning

Pruning is not indicated or recommended for species of this genus. Maintenance is carried out by eliminating dry or damaged branches to prevent them from becoming the focus of parasitic diseases.

In this regard, it is necessary to disinfect the tools used either by applying alcohol or fire, to prevent other tissues from becoming infected.

Spread

The multiplication of these plants occurs through seeds. These must be grown in pots or in seedbeds.

The seeds are planted at the end of winter, in February or March, using a fertile sandy substrate.

Trays with seeds or seedlings should be kept in the shade at a temperature of 18 ° C, ensuring constant humidity until the germination of the seeds is observed.

In the seedbed conditions, those plants that are not observed with a certain vigor must be eliminated to guarantee a better development of the plants that present more robustness.

Lobelia with pink flowers. Source: pixabay.com

Plagues and diseases

Small animals known as aphids are found in many species of Lobelia, which are commonly known as aphids. These animals can be controlled with specific products that are available in garden stores.

Another condition seen in these plants is yellowing of the leaves. This manifests as a splash of brownish-yellow spots, with subsequent curling of these leaves that ultimately fall to the ground.

Also, cobwebs can be seen on the underside of the leaves. In this case, the attack is by mites, the spider mite or spider mite. Here, the treatment can begin with the increase of the nebulisations or aspersions, since the lack of humidity favors the development of these animals; however, when the infestation is severe, specific chemicals must be used.

References

1. Chiapella, J., Tressens, S. 1997. Lobelia (Campanulaceae-Lobelioideae): new citations and key to the Argetinian species. Bonplandia 9 (3/4): 245-250.
2. Tropics. 2019. Lobelia L. Taken from: tropicos.org
3. Vieira, A. 1988. Taxonomic studies of species of Lobelia L. (Campaulaceae Juss.) That occur in Brazil. Dissertação (master) - State University of Campinas, Institute of Biology, Campinas. Taken from: repository.unicamp.br
4. Catalog of Life: Annual Ckecklist 2019. Lobelia L. Taken from: catalogueoflife.org
5. Miller, R. 1995. The magical and ritual use of herbs. Lasser Press Mexicana, SA Mexico, pages 39-40. Taken from: books.google.co.ve
6. Elicriso: magazine about the environment and nature. 2018. How to grow and cure Lobelia plants. Taken from: elicriso.it
7. Dictionary of medical sciences, by a society of the most famous professors in Europe. 1824. Lobelia. Madrid. Taken from: books.google.co.ve
8. Plant Flower. 2016. Lobelia: Characteristics, Cultivation and Care. Taken from: flordeplanta.com.ar
9. CONABIO. 2009. Campanulaceae or Lobeliaceae: Lobelia gruina Cav. Maria's Flower. Taken from: conabio.gob.mx
10. CONABIO. 2009. Campanulaceae or Lobeliaceae: Lobelia fenestralis Cav. Foxtail. Taken from: conabio.gob.mx
11. Infojardín. 2019. Lobelia, horse killer, Indian tobacco, asthma herb, Indian tobacco. Taken from: infojardin.net
12. Herbwisdom. 2019. Lobelia (Lobelia inflata). Taken from: herbwisdom.com