Colchicum autumnale: description, care, properties, toxicity, and interesting facts

Introduction

Colchicum autumnale, popularly known as colchicum, wild saffron, quitameriendas or autumn crocus, is a bulbous plant of great interest both ornamental and medicinal. This species, appreciated for its spectacular autumn flowering and its resistance, is also recognized for its toxicity and its use in traditional and modern medicine. In this article you will discover in detail all its Morphological characteristics, habitat, life cycle, properties, medicinal uses, cultivation methods, toxicity and curiosities most relevant, integrating in a single resource the most up-to-date and complete information derived from the main expert sources.

Botanical description of Colchicum autumnale

• Scientific name: Colchicum autumnal L.
• Common names: Colchicum, wild saffron, autumn crocus, nightshade, bastard saffron, wild onion, autumn colchicum, shepherd's dispatch, autumn flower, matacan, villorita, seedbeds.
• Family: Colchicaceae (formerly classified within the Liliaceae).
• Type: Perennial herbaceous plant, bulbous (more specifically tuberobulbous or cormous).
• Level: Between 15 and 30 cm, although it can reach up to 25 cm in optimal conditions.

El corm The underground bulb is rounded or sometimes pear-shaped, with leathery tunics, dark brown, reddish or blackish in color. From it emerge several solitary, hermaphrodite, trimerous and actinomorphic flowers with a perianth formed by six tepals soldered at the base, producing a long, narrow tube of violet, purplish-pink, or even whitish color. Each flower has six stamens, with yellow or purplish anthers, and a fruit in a globose capsule which remains almost underground until the seeds ripen.

The leaves, all basal, emerge after flowering, are linear or linear-lanceolate, flat, bright green, and glabrous in texture. They usually appear three to five times per bulb and can measure 18 to 35 cm in length, not developing during the flowering period.

Morphology and life cycle

The Colchian passes through a curious life cycleIt blooms in autumn, producing one to three flowers per bulb that emerge directly from the soil before the leaves, which is why they are known as "naked ladies" in English. After flowering, which usually occurs from late summer to early autumn, the flowers disappear, and in late winter or early spring, the leaves emerge, remaining until they yellow and dry when the bulb goes dormant.

1. Flowering: From August to November, depending on altitude and climate.
2. Leaves: Emergence after flowering. They persist until drying out (at which point the bulb requires a dry rest).
3. Fruit: Underground capsule containing several rounded seeds, dispersed mainly by ants (myrmecochory).

This alternation between flowering and leaf development allows it to take advantage of water and light resources in its natural habitat, which are usually wet meadows or forest clearings.

Geographic distribution and habitat

El Colchicum autumnal It is native to the eastern shores of the Black Sea and has spread widely throughout Europe, from Portugal to Ukraine, naturalizing in various areas. It is the only native species of the family in several regions of northern Europe and is also found in the Mediterranean basin and North Africa.

Su the habitat favorite are the wet meadows, forest clearings, mountain pastures, ditches, and streambanks, especially in deep, cool, and well-drained soils. It prefers altitudes that can provide regular moisture, from 450 to 2.000 meters above sea level, which allows it to sustain its life cycle without significant water stress.

Ecological conditions and adaptations

• Light: It tolerates full sun to partial shade. Although it grows best in full light, it can survive in slightly shaded areas.
• Temperature: It adapts well to temperate and mountainous zones, resisting frost, as long as the bulb is protected underground.
• Ground: It prefers alkaline-rich soils with a pH between 5.5 and 8, good moisture, and excellent drainage. It is an indicator of alkalinity and low in nitrogen.
• Salinity: It does not tolerate the presence of salts.

It is considered a plant geophyte, since their replacement organs (corms, rhizomes or bulbs) remain underground during the unfavorable period.

Care and cultivation of Colchicum autumnale

• Exhibition: Sunny or semi-shady location, avoiding dense shade.
• Substratum: Fertile, deep, cool, and well-drained soil. It tolerates neutral or calcareous soils, but not waterlogging.
• Irrigation: Frequent watering during flowering, keeping the humidity level low. When the leaves turn yellow, stop watering completely until regrowth occurs (to prevent bulb rot).
• Subscriber: It is not usually necessary if the soil is fertile, although it can benefit from adding compost before planting.
• Plantation: Autumn-flowering bulbs are planted in late summer, burying them about 7-10 cm deep and leaving about 15 cm between them. Spring-flowering bulbs are planted in late autumn.
• Maintenance: After flowering and once the leaves dry, it is advisable to remove the leaf debris to keep the bulb dormant.

• Multiplication: Mainly by division of corms after flowering (20-30 days after) or at the end of winter by separating the bulbous offspring. Less frequently by seed, although the seed requires stratification.

Ornamental uses and gardening

The colchicum is highly valued for its unexpected flowering in late summer and autumn, when most of the plants have disappeared, providing patches of violet, pink, or white that beautify gardens. It is used in:

• Grass clumps, herbaceous tapestries and borders.
• Rockeries and natural meadows.
• Pots and planters in patios and terraces.
• Cut flower, although its duration is limited outside the plant.

Certain varieties and selections have received awards for their ornamental merit in gardening. The plant is especially attractive in low-maintenance designs and wild gardens.

Propagation and reproductive cycle

• By division of corms: This is the simplest and quickest method. Once flowering is complete, the corms can be divided, separating the shoots and planting them immediately.
• By seed: Less common, as it requires stratification in cold conditions to germinate and can take several years to flower.

The seeds are dispersed mainly by myrmecochoria (ant transport), helping the natural expansion of populations in meadows and forest clearings.

Plagues and diseases

El Colchicum autumnal is characterized by being a resistant plant, although it can occasionally be attacked by pests such as Bedbugs and, in some cases, in excessively wet soils, bulb rot caused by fungi and bacteria. It is essential to avoid overwatering and keep the plant in well-drained soil to minimize these risks.

It doesn't usually require phytosanitary treatments, and few diseases seriously affect its development. Its potent toxicity acts as a biological defense against most predators.

Chemical composition and alkaloids

From a biochemical point of view, colchicum stands out for its content in isoquinoline alkaloidsfundamentally colchicine (around 0,6%), but also cornigerin, demecolcine, colchicilline, colchifolia, and other compounds. Colchicine is a light-sensitive alkaloid whose tricyclic structure inhibits microtubule formation, which explains its antimitotic effect and the formation of polyploidy in plant breeding experiments.

Alkaloids are present throughout the plant, particularly in seeds and bulbs. Toxicity is due to both colchicine and other related derivatives, and remains active even after the plant organs have dried.

Medicinal and pharmacological properties

• TraditionallySince ancient times, colchicum has been used for its properties anti-inflammatory and analgesicDioscorides already mentioned its high toxicity and medicinal uses in Roman Greece.
• Current use in medicine: Colchicine, extracted from the seeds and bulbs, is a valuable drug for the treatment of gout and microcrystalline arthritis (mainly induced by sodium urate crystals), as well as for familial Mediterranean fever and other diseases with an inflammatory component, such as scleroderma and primary biliary cirrhosis.
• Laboratory applications: In plant cytogenetics, colchicine is used to induce polyploidy and block cells in metaphase, making it useful in plant breeding and cell biology studies.
• Other effects: Cathartic, emetic, and antimitotic at the cellular level. It has also been used in homeopathy, although always under strict medical supervision due to its toxicity.

Warning: Medicinal use should be supervised by healthcare professionals, as colchicine has a very narrow therapeutic index; even slightly elevated doses can be lethal.

Toxicity and precautions

El Colchicum autumnal It is one of the most toxic plants in the European flora, especially due to its colchicine content. Both the bulbs as seeds They contain high concentrations of alkaloids. Ingesting as little as 10 mg of colchicine can be toxic, and doses above 40 mg are fatal for adults.

• Symptoms of poisoning These include difficulty swallowing, excessive salivation, abdominal pain, diarrhea, vomiting, muscle cramps, hypotension, respiratory disorders, and eventually kidney and multi-organ failure. The latency period can last several hours, with extremely severe progression and no specific antidote.
• Accidental ingestion is especially dangerous due to its superficial resemblance to edible plants such as saffron (Crocus sativus) or wild garlic (Allium ursinum), with which it should not be confused.
• In the legislation of many countries it is free sale prohibited of the plant, bulbs and seeds, and their handling requires expert manipulation.

In case of poisoning, treatment is only symptomatic and requires urgent medical intervention.

Ecological importance and conservation

Despite its toxicity and intensive use, Colchicum autumnale is considered a species of least concern It is listed on most red lists, with stable populations throughout much of its range. However, the combination of overharvesting, habitat destruction, and confusion with other edible species requires responsible protection and conservation standards.

Some populations in northern Europe are under protection, and Its conservation is essential for maintaining biodiversity of meadows and damp forest clearings.

Curiosities and etymology

• The name “quitameriendas” It refers to the flowering period at the end of summer, when the days become shorter and the number of days spent working outdoors is reduced, “taking away the snack” from the day laborers.
• Colchicum It derives from the Greek "Kolchís", a region on the eastern coast of the Black Sea, where the plant was abundant and feared for its poison according to Dioscorides.
• In English gardens it is known as “naked ladies” because of its leafless flowers.
• The resemblance to real saffron has led to accidental poisonings throughout history.
• In plant breeding, colchicine's ability to produce polyploids is highly valued in agriculture and genetics.

Glossary of associated terms

• Bulb: Underground reserve organ, with modified cataphylls or leaf bases.
• Tepals: Pieces of the perianth that are not differentiated into petals and sepals.
• Myrmecochoria: Seed dispersal by ants.
• Geophyte: Plant with persistent underground organs.
• Antimitotic: Substance that prevents cell duplication.
• Cathartic: It causes bowel movements.
• Emetic: It causes vomiting.

Bibliography and references

• “Disturbance indicator values ​​for European plants”, Midolo G., Herben T., Axmanová I., et al.
• “Ellenberg-type indicator values ​​for European vascular plant species”, Tichý L., Axmanová I., et al.
• Iberian Flora, Vol. XX. Liliaceae-Agavaceae.
• Plants and Fungi – Herbarium: https://www.plantasyhongos.es/herbarium/htm/Colchicum_autumnale.htm
• Asturnatura: https://www.asturnatura.com/especie/colchicum-autumnale
• Guadarramistas: http://guadarramistas.com/2015/10/23/colchicum-autumnale-colquico/
• Shanghai Nurseries: https://www.viverosshangai.es/Azafran-silvestre
• Elguadarramista: https://elguadarramista.com/2022/09/23/la-quitameriendas-tine-de-morado-el-otono/

The combination of its beauty, adaptability, pharmacological properties and associated risks make it Colchicum autumnal A unique and fascinating plant, ideal for those seeking low-maintenance species in the garden, with the added benefit of its extraordinary scientific and cultural value. Careful handling and knowledge of its characteristics ensure that it can continue to be part of our natural and botanical heritage, both in ornamental and pharmacological fields.