Cyclamen is Medieval Latin, from earlier Latin cyclamīnos, from Ancient Greek kyklā́mīnos (also kyklāmī́s), probably from kýklos "circle", because of the round tuber. In English, the species of the genus are commonly called by the genus name.
In many languages, cyclamen species are colloquially called by a name like the English sowbread, because they are said to be eaten by pigs: pain de pourceau in French, pan porcino in Italian, varkensbrood in Dutch. Sometimes they are called Persian violet or primrose, although it is unrelated to the violets and is not a primrose (Primula).
Description
Cyclamens have a tuber, from which the flowers and roots grow. In most species, leaves come up in autumn, grow through the winter, and die in spring, then the plant goes dormant through the dry Mediterranean summer.
Tuber
The storage organ of the cyclamen is a round and somewhat flattened tuber; it develops from the hypocotyl (the stem of a seedling).
The cyclamen storage organ is often informally called a corm. In botany, a corm (found in crocuses) is defined as having a papery tunic and a basal plate from which the roots grow, but the storage organ of the cyclamen has no papery covering and, depending on the species, roots may grow out of any part. Therefore, the cyclamen's storage organ is properly classified as a tuber (somewhat like a potato).
The tuber may produce roots from the top, sides, or bottom, depending on the species. Cyclamen persicum and Cyclamen coum root from the bottom; Cyclamen hederifolium roots from the top and sides. Cyclamen graecum has thick anchor roots on the bottom. Leaves and flowers sprout in rosettes from growing points on the top of the tuber. If the growing points lengthen and become like woody stems, they are known as floral trunks.
In older specimens of Cyclamen purpurascens and Cyclamen rohlfsianum, growing points on the tuber may become separated by shoulders of tissue, and the tuber may become misshapen. In most other species, the tuber is round in old age. The size of the tuber varies depending on species. In Cyclamen hederifolium, older tubers commonly reach 24 cm (9.4 in) across, but in Cyclamen parviflorum, tubers do not grow larger than 2 cm (1 in) across.
Flowers
Flowering time may be any month of the year, depending on the species. Cyclamen hederifolium and Cyclamen purpurascens bloom in summer and autumn, Cyclamen persicum and coum bloom in winter, and Cyclamen repandum blooms in spring.
Each flower is on a stem coming from a growing point on the tuber. In all species, the stem is bent 150-180° at the tip, so that the nose of the flower faces downwards. Flowers have 5 petals, bent outwards or up, sometimes twisted, and connected at the base into a cup, and five sepals behind the cup.
Petal shape varies depending on species, and sometimes within the same species. Cyclamen repandum has petals much longer than wide, Cyclamen coum has stubby, almost round petals, and Cyclamen hederifolium usually has petals with proportions between the two. Petal color may be white, pink, or purple, often with darker color on the nose. Many species have a pink form and a white form, but a few have only one color, such as Cyclamen balearicum, which is always white.
The dark color on the flower nose varies in shape: Cyclamen persicum has a smooth band, Cyclamen hederifolium has a streaky V, and Cyclamen coum has an M-shaped splotch with two white or pink "eyes" beneath.
In some species, such as Cyclamen hederifolium, the petal edges at the nose are curved outwards into auricles (Latin for "little ears"). Most species, like Cyclamen persicum, have no auricles. In most species, the style protrudes 1–3 mm out of the nose of the flower, but the stamens are inside the flower. In Cyclamen rohlfsianum, however, the cone of anthers sticks out prominently, about 2–3 mm (0.08–0.12 in) beyond the rim of the corolla, similar to shooting-stars (Dodecatheon).
The flower stem coils or bends when the fruit begins to form. The stems of Cyclamen hederifolium and Cyclamen coum coil starting at the end, Cyclamen persicum arches downwards but does not curl, Cyclamen rohlfsianum coils starting near the tuber, and Cyclamen graecum coils both directions, starting at the middle.
The fruit is a round pod that opens by several flaps or teeth at maturity and contains numerous sticky seeds, brown at maturity. Natural seed dispersal is by ants (myrmecochory), which eat the sticky covering and then discard the seeds.
Cultivation and uses
Cyclamen are commonly grown for their flowers, both outdoors and indoors in pots. Several species, particularly Cyclamen hederifolium, are hardy and can be grown outdoors in mild climates such as northwest Europe and the Pacific Northwest of North America.
The cyclamen commonly sold by florists is C. persicum, which is frost-tender. Selected cyclamen cultivars can have white, bright pink, red or purple flowers. While flowering, florists' cyclamens should be kept below 20 °C (68 °F), with the night time temperatures preferably between 6.5 °C to 15 °C (44 °F to 59 °F). Temperatures above 20 °C (68 °F) may induce the plant to go dormant. Cyclamens bloom in different seasons, depending on the species.
Conservation
In many areas within the native range, cyclamen populations have been severely depleted by collection from the wild, often illegally, for the horticultural trade; some species are now endangered as a result. However, in a few areas, plant conservation charities have educated local people to control the harvest carefully at a sustainable level, including sowing seed for future crops, both sustaining the wild populations and producing a reliable long-term income. Many cyclamen are also propagated in nurseries without harm to the wild plants.
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