I have to admit that I am a newcomer to the world of crocuses, know very little about them, except that they are one of the first flowers to herald the Spring, and tend to get a bit confused about all the different types, so I thought a bit of research and consequently a feature post might be in order!
The first surprising fact, which I discovered in my research was that these tiny little bulbs belong to the Iris family Iridaceae (see photo above); there are 90 species (though recent chromosome tests have increased the number of species to almost 200) and only 30 species are in cultivation; there are many crocus species, which also bloom in Autumn and Winter; and crocus enthusiasts are known as ‘croconuts’!!! I suspect that after this wonderful season, I could well become one!Their name derives from the Greek word ‘Krokos’, meaning ‘saffron’, referring to the long history of the cultivation of Crocus sativum over 2000 years for the production of the spice saffron for a yellow dye, food colourant, culinary spice and medicinal purposes. The large lilac Autumn flowers have darker veins on the petals, yellow stamens and three vivid red stigma, the source of the saffron.
It is the most expensive spice in the world, 1 Kg of saffron requiring the handpicking of over 85 000 flowers between dawn and 10am and costing $35 000 per Kg! Mind you, both those figures (number of flowers required and cost) vary widely, depending on which article you read! All I know is that in both cases, it’s a lot!!! I found an interesting link about saffron growing in Australia at: https://www.smh.com.au/lifestyle/man-with-the-golden-thumb-20080812-gdsq4i.html.
Crocuses (or Croci) are native to Central and Southern Europe; North Africa and the Middle East; the Aegean islands and Central Asia to China. They grow from corms and have narrow mid-green grass-like leaves with a central silver grey stripe and white, lavender, lilac, purple and yellow cup-shaped six-petalled flowers, which have a short stem, long tube, three stamens and one style and only open in the sun or bright light, remaining closed in rainy weather or at night.The corms should be planted 3 to 4 cm deep in sandy well-drained soils in a sunny position. They look lovely in drifts or clumps and naturalise well in lawns, though the grass should not be cut for 6 weeks after flowering to ensure blooming the following year.There are a number of different species, many of which can be seen on : https://www.pacificbulbsociety.org/pbswiki/index.php/Crocus. Another excellent link is: https://gardendrum.com/2014/02/27/crocus-for-autumn-winter-and-spring/.
The name of EA Bowles kept cropping up in my research into crocus, both in relation to his breeding of them and in the naming of new cultivars and if you would like to know more about his endeavours, especially in relation to crocuses, it is well worth reading: https://thedahliapapers.com/tag/crocus-e-a-bowles/.
The cultivated crocus species can be divided into two main groups according to their flowering season.
Crocus sieberi Cretan Crocus. Small flowers start blooming in late Winter as the snow melts. It naturalises easily. Cultivars include Bowles White; Firefly (lilac); Tricolor (white to pale lilac with dark lilac edge and gold centres); and Violet Queen. The species name ‘sieberi’ honours Franz Wilhelm Sieber (1789-1844), a natural history collector and traveller from Prague.
Crocus chrysanthus Snow Crocus. Native to Yugoslavia, Romania, Greece and Southern Turkey, it flowers in bare earth or the snow on stony or grassy slopes at 1000 to 2000 metres altitude in early Spring. It has smaller, but more profuse flowers than the Dutch crocus and unusual color blends, many hybrids having bicoloured petals and striking yellow centres. The species name ‘chrysanthus’ means ‘golden flowers’. Hybrid cultivars include Cream Beauty; Dorothy; EA Bowles; Goldilocks and Gipsy Girl.
Crocus tommasinianus Early Crocus. Blooms from late Winter to early Spring with pale lavender to red purple blooms with a silvery reverse. They flower profusely after the leaves have fully developed and spontaneously self-propagate, so are very good at naturalising in lawns. The species hails from the woods and shady hillsides of Southern Hungary, Yugoslavia and Northern Bulgaria is named after Muzio Giuseppe Spirito de Tommasini (1794-1879), an Italian botanist and expert on Dalmatian flora from Trieste. They can be distinguished from C. vernus by its combination of narrow leaves, purple flowers and white tube.
Crocus vernus Dutch Crocus. Very popular and well-known, these tough crocus have the largest flowers of all, so they are sometimes known as Giant Crocus. Originally from the mountains of Europe from the Pyrenees east to Poland and Russia and south to Sicily and Yugoslavia, they flower from early Spring. They will tolerate light shade, like under deciduous trees, in temperate areas. ‘Vernus’ means ‘of the Spring’. I have planted five varieties:
Jeanne d’Arc: Pure white (photo above);
Mammoth: Golden yellow;
Pickwick 1925: Striped white and purple (photo below);
Remembrance: Violet-purple; and
Grand Maître: Purple and blooms slightly later in Spring.
There are also yellow and bronze varieties.My first attempt at growing Dutch crocuses in 2016 yielded a single purple flower, about which I was very excited as its appearance was a total surprise! I had planted ten corms (4 Mammoth and 6 Remembrance) the previous Autumn (mid-April) in the lawn under the deciduous trees, but had not been aware of the emergence of the leaves, when suddenly there was this bright purple flower in July!
I searched in vain for any further flowers that season, as well as the following year, so I was delighted when again a further bud snuck in under the radar, as well as a second grouping of crocus leaves. They are definitely reproducing. Imagine my horror to discover the new bloom nipped in the bud literally by a voracious Satin Bowerbird male and there were no more Remembrance blooms this season!
Luckily, at the end of April this year, I also planted 5 Jeanne d’Arc; 5 Pickwick; and 10 Grand Maître (photo below) corms in the cutting garden in well-noted spots. The foliage of most of them had surfaced by mid-August and they bloomed spectacularly in the first two weeks of September.Two good places to source species crocus in Australia are Lambley’s Nursery at: https://lambley.com.au/garden-notes/winter-crocus and https://lambley.com.au/search/content/crocus(6 pages)
And Bryan H Tonkin : https://www.tonkinsbulbs.com.au/crocus.html, while Tesselaars has a good range of Snow Crocus (https://www.tesselaar.net.au/product/4010-snow-crocus-collection) and Dutch Crocus (https://www.tesselaar.net.au/naturalising-bulbs/dutch-crocus).
There are still quite a large number of Crocus (at least 30 species and subspecies) which flower in Autumn, the most famous of which is Crocus sativum, the Saffron Crocus, the species name ‘sativum’ meaning ‘cultivated’.
Please note that there are two other genera, Colchicum and Zephyranthes, which are also called Autumn Crocus.
Colchicums, a distant relative of crocus and also a corm, can be differentiated from crocus by the number of styles and stamens. Colchicums have large strappy leaves without a stripe and pink, lilac or white six-petalled flowers (Colchicum luteum from Turkey is the only yellow one) with three styles and six stamens, compared to crocus flowers with their one style and three stamens.
Colchicum flowers also emerge from the soil before the leaves appear, thus their alternative name Naked Ladies, while in Spring-blooming crocus species, leaves shoot first or simultaneously with the flowers. Autumn flowering crocus bloom in full leaf. An exception is Crocus speciosus, whose flowers are produced before the leaves.
Most colchicum species bloom in Autumn (eg lilac-pink Meadow Saffron, Colchicum autumnale, and Colchicum speciosum with its lilac-pink flower with a white throat or its pure white cultivar Album), but a few emerge in Spring (Colchicum szovitsii; Colchicum falcifolium; Colchicum kesselringii; Colchicum hungaricum; and Colchicum luteum).
Members of the Liliaceae family with 45 species from Eastern Europe to North Africa and east to China, most of the colchicums found in Australia hail from Turkey and Greece. According to ancient writers, colchicums were particularly abundant around Colchis, the Black Sea region of Georgia, Caucasus, hence its name. Photographs of the different species can be found on: https://www.pacificbulbsociety.org/pbswiki/index.php/Colchicum.
They like similar conditions to crocus- well-drained soil in full sun or part shade and cool to cold climates with frosty Winters. They can also be bought from Bryan H Tonkin (https://www.tonkinsbulbs.com.au/colchicum.html) and Lambleys Nursery (https://lambley.com.au/search/content/colchicum).
All species and parts of the plant are toxic and the sap can irritate the skin and eyes, so take care handling them! Having said that, it is also the source of the cancer treatment drug colchicine, a mutagen which affects cell division and is also used by plant breeders to produce new cultivars.
Zephyranthes, a New World genus from the Amaryllidaceae (Hippeastrum) family, is also called Rain or Storm Lilies as summer and autumn showers trigger flowering. The genus name derives from two Greek words: ‘zephyros’ meaning ‘west wind’ and ‘anthos’ meaning ‘flower’, since it is a native of the Western Hemisphere (the Americas) and includes 70 species, some of which can be seen in: https://gardendrum.com/2013/01/13/storm-lilies/.
They prefer cool frost-free and subtropical gardens. Having said that, we grow Zephyranthus candida in the shade of the Pepperina tree, where it retains its foliage all year round. In fact, we sourced our bulbs from my sister’s Tenterfield garden, where she gets heavy frosts and temperatures of ten degrees below zero!Zephyranthes candida hails from Uruguay and Argentina. It has bright green glossy needle-like leaves and shining white crocus-like flowers with gold stamens.Sternbergia
To further complicate the issue, the genus Sternbergia, is also called Autumn Crocus, as well as Autumn Daffodil, and there are eight species, distributed from Italy to Iran. The genus is named in honour of Count Kaspar M von Sternberg (1761-1838), an Austrian clergyman, botanist and palaeontologist and founder of the Bohemian National Museum in Prague.
Most bloom in Autumn, the fine narrow leaves emerging with or just after the flowers, though there are some species which bloom in Spring (Sternbergia fischeriana; Sternbergia colchiciflora; and Sternbergia candida). For more information about and photos of the different species, see: https://www.pacificbulbsociety.org/pbswiki/index.php/Sternbergia.
Sternbergia lutea is the most well-known one, its species ‘lutea’ name meaning ‘yellow’. It has a similar appearance to colchicums, except its bright canary-yellow flower colour. There is only one flower per bulb and they prefer frost-free gardens and a hot dry Summer.
I certainly know so much more about crocus now and am keen to experiment with a few other crocus varieties like Crocus sativus and some of the Snow Crocus cultivars in the cutting garden or rockery and perhaps to try naturalising the apparently foolproof and fecund Crocus tommasinianus in the lawn ! I would also love to try growing Sternbergia lutea in a pot in a frost-free position up by the house.