This section is from the book "British Wild Flowers - In Their Natural Haunts Vol5-6", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
This plant is quite unknown except from its present-day distribution, which is from Belgium southwards to Lombardy and Hungary. It is native in these islands only at its single locality in North Somersets, on the rocks of Cheddar Gorge, and it is only introduced in Oxford and Edinburgh; and in Northampton, West Gloucester, South Lincs, and Westmorland it is erroneously recorded as native.
Cheddar Gorge, which is a valley cut through Carboniferous rocks and calcareous, is the only locality for this charming pink, called from its single British station the Cheddar Pink. In the minds of the country traveller and the botanist this locality is thus rendered doubly famous, first for the reputed Cheddar Cheese, and last, but not least, for the Cheddar Pink. Over the limestone rocks at this place it grows in patches like Thrift at the seaside; but this plant is eminently a lime-loving plant, the other sand-loving.
Like other pinks and carnations, e.g. the Common Clove, the Cheddar Pink grows in tufts on the rocks, having a woody rootstock and numerous stems. The leaves are linear, blunt, with rough edges, bluish-green, and the barren stems are much branched.
The flower-stalks are usually single, in panicles or solitary. The petals are rosy, inversely egg-shaped, notched, downy. The calyx scales are roundish, blunt, only 1/4 as long as the calyx and pressed close together, and the flower is scented.
The plant is not more than 3 in. high when barren, the flowering stems are 6-8 in. It is in bloom in June and July. Like others of the group it is perennial, and increased by cuttings.
Honey-glands in D. deltoides, the pollination of which is similar to that of this plant, are formed by the union of petals and stamens at the base. The stamens and pistil nearly close the narrow tube, making it impossible for any but moths to get at the honey. Other insects, such as flies, are pollen-seekers. The flower is conspicuous, being flattened above. There are 10 stamens. Five project, and the anthers open when the flower opens, and ripen, and after the pollen is shed the other five do so. After they have all opened, the pistil, previously concealed, emerges, and the 2 long stigmas elongate. In this way it is necessary for Lepidoptera to convey pollen from anthers of young to the stigmas of old flowers. The plant is not self-pollinated. It is sweet-scented. Some plants produce only female flowers.
The seeds of the Cheddar Pink are dispersed by the wind. The capsule opens to form a series of apical teeth and allows the seeds to be dispersed by the wind, the stem swaying backwards and forwards.
A fungus, Ascochyta dianthi, infests several members of the Clove and Pink tribe. The beetle Phytonomus polygoni feeds on it.
This is a lime-loving plant, and saxicolous, requiring a lime soil and growing on rocks.
Dianthus is the name given by Linnaeus, Greek Dios anthos, Flower of Jove, and glaucus means bluish-grey or glaucous, in allusion to its colour.
Cheddar Pink is called Cleve-pink, Cliff-pink. Cleve-pink is given in the same sense as Cliff-pink, both indicating its habitat, and the first its only locality.
It has been cultivated as a flower in the garden for the rock-border. Essential Specific Characters: 46. Dianthus glaucus, Huds. - Leaves linear, with rough margins, flowers solitary, rose-pink, petals bearded, jagged, bracts shorter than the calyx.