DROSERA CAPENSIS: CHARACTERISTICS, HABITAT, CULTIVATION, CARE - BIOLOGY - 2024

The Drosera capensis is a rhizomatous perennial carnivorous species belonging to the family Droseraceae. Known as sundew or drop grass, it is an insectivorous plant native to the Cape Province in Africa.

It is a herbaceous plant that measures between 20-30 cm high, with elongated leaves covered with trichomes that secrete a mucilage that traps insects. The flowers are arranged on a long floral scape, have the ability to self-pollinate and generate numerous seeds that are dispersed by the wind.

Drosera capensis. Source: H. Zell

Its tentacle-shaped leaves are covered in mucilaginous trichomes that trap insects and then digest them with their enzymes. At minimal contact, the leaves are activated and envelop the prey, initiating the digestion process that lasts 5 to 6 hours.

This easily propagated species adapts to different environmental conditions, from hot and open places to shady and cold environments. It is a perennial plant that lives for several years thanks to its easy propagation by seeds or suckers that emerge from the base of its central rosette.

It has traditionally been used as an ornamental plant, and today it is still made from fresh leaves of Drosera capensis, a liquor known as "sun dew." In addition, it has medicinal properties, since its extract contains «plubagine», an antibiotic principle that fights bacteria and viruses, used to cure colds, flu and respiratory diseases.

General characteristics

Appearance

Annual or perennial herbaceous plant with antenna or tentacle shaped leaves that can reach up to 30 cm in height. Its sensitive and highly mobile leaves have the ability to digest the nutrients of insects that are trapped with their glandular trichomes.

Leaves

The elongated 5-7 cm long leaves are covered by glandular hairs or trichomes that secrete a viscous and sweetish mucilage containing glandular cells. Its main function is to immobilize the insects that land on the leaves and then be digested by proteolytic enzymes.

flowers

This species develops 40-50 light violet or pinkish flowers 1-2 cm in diameter on a 30-35 cm long floral scape. Flowering occurs during the summer, the flowers tend to open individually in the morning, to close again at the end of the afternoon.

Drosera capensis flowers. Source: Peter Presslein

Fruit

The flowers of Drosera capensis self-pollinate, developing a dried fruit known as a dehiscent loculicidal capsule that contains a large number of small seeds. Under suitable environmental conditions, the seeds tend to disperse easily giving rise to new seedlings around the mother plant.

Digestion

Drosera capensis is a carnivorous plant that traps prey through digestive secretions that it emits from the tentacles of the leaves. These droplets are a visual signal that shines through the crystalline tip of the trichome. It also behaves as a chemical agent that attracts prey.

When the insect is immobilized by the slimy tentacles, the leaves fold and surround the prey, while the mobile tentacles prevent the prey from escaping. The plant acts as an external stomach, which secretes digestive enzymes that break down the prey's proteins and form a nutritious slurry that is absorbed at the cellular level.

The digestion process lasts approximately 5-6 hours, during which time the nutrients extracted from the prey are absorbed by the tips of the tentacles. The soft parts of the prey are generally digested, leaving only the cuticle on the tentacles of the leaves. In the following video you can see how a fly catches:

Taxonomy

- Kingdom: Plantae

- Division: Magnoliophyta

- Class: Rosopsida

- Order: Caryophyllales

- Family: Droseraceae

- Genus: Drosera

- Subgenus: Drosera

- Section: Drosera

- Species: Drosera capensis L.

Leaves and trichomes of Drosera capensis. Source: pixabay.com

Etymology

- Drosera: the name of the genus comes from the Greek «δρόσος» (droso) which means «dew or drops of dew». Alluding to the small drops of mucilage located at the end of each leaf.

- capensis: the specific adjective refers to the geographical place where it was initially described, the Cape Province in South Africa.

Varieties

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This variant of the species Drosera capensis has vibrant pink tentacles in full sun exposure. In partial shade, the leaves are whitish or have an "albino" appearance. Easily reproduced by the tray method.

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Variety that develops bright red leaves if they remain in full sun exposure. At maturity, the leaves grow to 6 cm long, it adapts to indoor conditions and, during its adult stage, does not require feeding to maintain its development.

- Drosera capensis «bains kloof»

Small carnivorous plant. It is characterized by its small leaves, only slightly wider than the typical variety. The greenish-yellow leaves have long, reddish tentacles.

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Variety characterized by its 4-5 cm wide leaves, although when they are not fed the size may be smaller. Lighting, temperature, moisture arrangement and nutritional elements are essential to determine the thickness of the petioles.

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Variety that can reach 50-60 cm in height. Its petioles show a higher growth compared to the typical species of Drosera capensis.

Detail of the trichomes of Drosera capensis. Source: Michal Rubeš

Habitat and distribution

Native to Cape Town in South Africa, today it is a plant cultivated around the world due to its great adaptability and easy propagation. Their natural habitats are swamps, stream or creek banks, infiltrated lands, and humid areas in biomes known as fynbos.

Indeed, the fynbos are a type of shrub vegetation characteristic of the Cape region. Where it rains only in winter and during summer fires are frequent.

Drosera capensis is wildly distributed mainly in South Africa. In Australia and New Zealand it is considered an invasive plant, so its commercialization is prohibited. It was introduced in these countries involuntarily in contaminated substrate.

Culture

Leaf of Drosera capensis. Source: pixabay.com

Requirements

- Requires abundant natural light. During the winter it can remain exposed to full sun exposure, while in summer it must be protected from the direct rays of the sun.

- The ideal temperature range for its development is between 5 and 28 ºC, although it tolerates occasional frosts or specific peaks of temperature higher than 35 ºC.

- It grows on not very fertile soils and requires high moisture content. Its long root system is continuously active, absorbing water from the substrate, so irrigation must be constant. It is advisable to use demineralized water.

- It can be grown in a nursery, greenhouse or outdoors and in different types of climate, whether tropical, subtropical, temperate or Mediterranean.

- The ideal medium for its cultivation is a mixture of moss and sand or silica in pots 10-15 cm deep. It is recommended to keep a tray with water permanently under the pot so that the substrate remains moist.

- In subtropical climates, the species can be cultivated throughout the year, as it does not require a period of rest or hibernation.

Reproduction

The Drosera capensis is a species of easy propagation, as much by seeds as cuttings of leaves or division of rhizomes. The simplest and most effective way is by means of seeds, which are characterized as having a high percentage of germination.

Leaf cuttings are obtained from healthy plants and the method consists of cutting pieces of leaves and sowing in fertile substrate. Propagation by division of rhizomes is done by the "water float" method, where the rhizomes are placed in demineralized water until new seedlings start to form.

Care

Insect trapped in Drosera capensis. Source: Rosťa Kracík

Location

The carnivorous plant "sundew" can be grown indoors or outdoors, in full sun exposure or partial shade. During cool seasons, when the solar radiation is not very intense, it can be kept exposed to the sun's rays in the morning or in the afternoon.

Rusticity

This species is of subtropical origin, which is why it is susceptible to intense frosts. During the winter it adapts to temperature ranges between 5-15 ºC and during the summer from 20-40 ºC.

In a warm Mediterranean climate, where the temperature drops to -2 ºC, it can be grown throughout the year. In areas with strong winters, it should be kept in a greenhouse or a warm and bright room until the beginning of spring.

Substratum

The best substrate for effective growth is made up of a mixture of moss or peat moss (70%) and non-calcareous sand or perlite (30%). The use of black peat, mulch, compost compost or black soil is not recommended, since the pH can alter the development of the root system.

Irrigation

Frequent watering with demineralized water is recommended, preferably rain, distilled or purified by osmosis. During the summer it is advisable to keep a tray with water under the pot and during the other seasons it can be watered 2-3 times a week, never leaving the substrate dry.

Subscriber

Drosera capensis does not require fertilization or fertilization, since its root system is not adapted to absorb nutrients and it would burn. Its form of nutrition is by trapping insects from which it absorbs nutrients through the glandular trichomes.

Plagues and diseases

This rustic plant usually has few natural enemies. In hot and dry environments it can be attacked by cottony mealybugs, which can be eliminated by physical methods with the use of a brush or small brush.

References

1. Chuet-Missé, JP (2017) This is the most lethal and fascinating carnivorous plant that is endangered by humans. The Natural Vanguard. Recovered in:vanaguardia.com
2. Drosera capensis. (2019). Wikipedia, The Free Encyclopedia. Recovered at: es.wikipedia.org
3. Drosera capensis (2018) Virtual Catalog of Plant Species. Jardí Botànic of the University of Valencia. Recovered in: jardibotanic.org
4. Espejo, C., de la Vega, BL, & Sánchez, T. (2013). Collection of insectivorous plants in La Concepción, Málaga. El / 0 botânico: AIMJB Magazine, (7), 20-22.
5. Jobson, RW, & Conn, B. (2012). Drosera capensis (Droseraceae), a new naturalized record for Australia. Telopea, 14, 89-92.
6. The Drosera Plants (2018) The Carnivorous Plants. Web specialized in carnivorous plants. Recovered in: lasplantascarnivoras.info
7. McQuillan, M. (2008) Drosera capensis L. © SA National Biodiversity Institute. Recovered at: pza.sanbi.org