When it seems like winter will never lose its icy grip, the dainty goblet-shaped crocus pushes through the snow to put on a show of colorful revival. If you are not planting this perennial bulb, you are missing an early season of delight.
Crocus (English plural: crocuses or croci) is a genus of flowering plants in the iris family comprising 90 species of perennials growing from corms. Many are cultivated for their flowers appearing in autumn, winter, or spring. Crocuses are native to woodland, scrub, and meadows from sea level to alpine tundra in central and southern Europe, North Africa and the Middle East, on the islands of the Aegean, and across Central Asia to western China.
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Asparagales
Family: Iridaceae
Subfamily: Crocoideae
Genus: Crocus
Etymology
The name of the genus is derived from the Greek κρόκος (krokos). This, in turn, is probably a loan word from a Semitic language, related to Hebrew כרכום karkōm, Aramaic kurkama, and Arabic كركم kurkum, which mean “saffron” ( Crocus sativus), “saffron yellow” or turmeric (see Curcuma). The English name is a learned 16th-century adoption from the Latin, but Old English already had croh “saffron”. The Classical Sanskrit कुङ्कुमं kunkumam “saffron” (Sushruta Samhita) is presumably also from the Semitic word.
History
Cultivation and harvesting of Crocus sativus for saffron was first documented in the Mediterranean, notably on the island of Crete. Frescos showing them are found at the Knossos site on Crete, as well as from the comparably aged Akrotiri site on Santorini.
The first crocus seen in the Netherlands, where crocus species are not native, were from corms brought back in the 1560s from Constantinople by the Holy Roman Emperor’s ambassador to the Sublime Porte, Ogier Ghiselin de Busbecq. A few corms were forwarded to Carolus Clusius at the botanical garden in Leiden. By 1620, the approximate date of Ambrosius Bosschaert‘s painting (illustration, below), new garden varieties had been developed, such as the cream-colored crocus feathered with bronze at the base of the bouquet, similar to varieties still on the market. Bosschaert, working from a preparatory drawing to paint his composed piece spanning the whole of spring, exaggerated the crocus so that it passes for a tulip, but its narrow, grass-like leaves give it away.
Description
The cup-shaped, solitary, salverform flower tapers off into a narrow tube. Their colors vary enormously, although lilac, mauve, yellow, and white are predominant. The grass-like, ensiform leaf shows generally a white central stripe along the leaf axis. The leaf margin is entire. Crocuses typically have three stamens. The spice saffron is obtained from the stigmas of Crocus sativus, an autumn-blooming species.
Autumn crocus
Some species, known as “autumn crocus”, flower in late summer and autumn, often before their leaves appear. They should not be confused with a different genus of autumn-flowering plants, Colchicum. Autumn-flowering species of crocus include:
- C. banaticus (syn. C. iridiflorus)
- C. cancellatus
- C. goulimyi
- C. hadriaticus
- C. kotschyanus (syn. C. zonatus)
|
- C. laevigatus
- C. ligusticus (syn. C. medius )
- C. niveus
- C. nudiflorus
- C. ochroleucus
|
- C. pulchellus
- C. sativus (saffron crocus)
- C. serotinus
- C. speciosus
- C. tournefortii
|
C. laevigatus has a long flowering period which starts in late autumn or early winter and may continue into February.
Species
The taxonomic classification proposed by Brian Mathew in 1982 was based mainly on three character states:
- the presence or absence of a prophyll (a basal spathe);
- the aspect of the style;
- the corm tunic.
The seven species discovered since then have been integrated into this classification.
Molecular analysis carried out at the University of Copenhagen suggests this classification should be reviewed. In particular, the DNA data suggest there are no grounds for isolating C. banaticus in its own subgenus Crociris, though it is a unique species in the genus. Because it has a prophyll at the base of the pedicel, it therefore would fall within section Crocus, although its exact relationship to the rest of the subgenus remains unclear.
Another anomalous species, C. baytopiorum, should now be placed in a series of its own, series Baytopi. C. gargaricus subsp. herbertii has been raised to species status, as C. herbertii. Perhaps most surprisingly, autumn-flowering C. longiflorus, the type species of series Longiflori (long regarded by Mathew as “a disparate assemblage”), now seems to lie within series Verni. In addition, the position of C. malyi is currently unclear.
DNA analysis and morphological studies suggest further that series Reticulati, Biflori and Speciosi are “probably inseparable”. C. adanensis and C. caspius should probably be removed from Biflori; C. adanensis falls in a clade with C. paschei as a sister group to the species of series Flavi; C. caspius appears to be sister to the species of series Orientales.
The study shows “no support for a system of sections as currently defined”, although, despite the many inconsistencies between Mathew’s 1982 classification and the current hypothesis, “the main assignment of species to the sections and series of that system is actually supported”. The authors state, “further studies are required before any firm decisions about a hierarchical system of classification can be considered” and conclude “future re-classification is likely to involve all infrageneric levels, subgenera, sections and series”.
Below is the classification proposed by Brian Mathew in 1982, adapted in accordance with the above findings:
- A. Section Crocus : species with a basal prophyll
-
- Series Verni: corms with reticulated fibers, spring-flowering (apart from Crocus longiflorus), flowers for the most part without conspicuous outer striping, bracts absent
-
- Series Baytopi (new Series): corms with strongly reticulated fibers; leaves numerous, narrowly linear; spring-flowering, bracts absent; anthers extrorsely dehiscent
-
- Series Scardici: spring-flowering, leaves have no pale stripe on the upper surface
-
- Series Versicolores: spring-flowering, corms with tunics, which for the most part have parallel fibers, flowers with conspicuous exterior striping
-
- Series Longiflori: autumn-flowering, yellow anthers, styles much divided
-
- Series Kotschyani: autumn-flowering, anthers white, styles for the most part three-forked
-
- Series Crocus: autumn-flowering, anthers yellow, style distinctly three-branched
-
- Position unclear [7]
- B. Section Nudiscapus: species without a basal prophyll
-
- Series Reticulati: corm tunic for the most part decidedly covered with reticulated fibers, flower produced in winter or spring, style three-forked or much divided
-
- Series Biflori: tunics of corms split into rings at the base, either entire or with toothlike projections, leathery in texture, spring- or late-winter flowering, style three-forked
- Crocus aerius Herb.
- Crocus almehensis C.D. Brickell & B. Mathew
- Crocus biflorus Mill. – silvery crocus, Scotch crocus
- Crocus biflorus subsp. biflorus
- Crocus biflorus subsp. adamii (J.Gay) K.Richt.
- Crocus biflorus subsp. alexandri (Nicic ex Velen.) B. Mathew
- Crocus biflorus subsp. artvinensis (J.Philippow) B. Mathew
- Crocus biflorus subsp. atrospermus Kernd. & Pasche
- Crocus biflorus subsp. caelestis Kernd. & Pasche
- Crocus biflorus subsp. caricus Kernd. & Pasche
- Crocus biflorus subsp. crewei (Hook.f.) B. Mathew
- Crocus biflorus subsp. fibroannulatus Kernd. & Pasche
- Crocus biflorus subsp. ionopharynx Kernd. & Pasche
- Crocus biflorus subsp. isauricus (Siehe ex Bowles) B.Mathew
- Crocus biflorus subsp. leucostylosus Kernd. & Pasche
- Crocus biflorus subsp. melantherus B. Mathew
- Crocus biflorus subsp. nubigena (Herb.) B. Mathew
- Crocus biflorus subsp. pseudonubigena B. Mathew
- Crocus biflorus subsp. pulchricolor (Herb.) B. Mathew
- Crocus biflorus subsp. punctatus B.Mathew
- Crocus biflorus subsp. stridii (Papan. & Zacharof) B.Mathew
- Crocus biflorus subsp. tauri (Maw) B. Mathew
- Crocus biflorus subsp. weldenii (Hoppe & Fuernr.) B. Mathew
- Crocus biflorus subsp. yataganensis Kernd. & Pasche
- Crocus chrysanthus Herb. – Golden crocus, Snow crocus
- Crocus chrysanthus subsp. chrysanthus
- Crocus chrysanthus subsp. multifolius Papan. & Zacharof
- Crocus cyprius Boiss. & Kotschy
- Crocus danfordiae Maw
- Crocus danfordiae subsp. danfordiae
- Crocus danfordiae subsp. kurdistanicus Maroofi & Assadi
- Crocus hartmannianus Holmboe
- Crocus kerndorffiorum Pasche (1993)
- Crocus leichtlinii (Dewar) Bowles
- Crocus nerimaniae Yüzbasioglu & Varol (2004)
- Crocus pestalozzae Boiss.
- Crocus wattiorum (B. Mathew, 1995) B. Mathew (2000)
-
- Series Speciosi: corm tunic splits into rings at the base, leathery or membranous, foliage after the flowers, autumn-flowering, style much divided
- Crocus pulchellus Herb. – hairy crocus
- Crocus speciosus M. Bieb. – Bieberstein’s crocus, large purple crocus
- Crocus speciosus subsp. ilgazensis B.Mathew
- Crocus speciosus subsp. speciosus
- Crocus speciosus subsp. xantholaimos B.Mathew
-
- Series Orientales: corm with parallel fibers or lightly reticulated, numerous leaves, spring-flowering, style three-forked
-
- Series Flavi: tunics of the corms membranous, split into parallel fibers, spring-flowering, styles much divided
-
- Series Aleppici: tunics of the corms membranous, with split, parallel fibers, foliage produced at the same time as the flowers, fall- or winter-flowering
-
- Series Carpetani: undersurface of the leaves rounded with grooves, upper surface channeled, spring-flowering, style whitish, obscurely divided
-
- Series Intertexti: corm tunic fibrous with fibers interwoven, spring-flowering
-
- Series Laevigatae: corm tunic membranous or splitting into parallel fibers, sometimes leathery, foliage produced at the same time as flowers, autumn-flowering, anthers white, style much divided