The Deptford pink is an upright plant, not unlike its garden relative Sweet-William in appearance. The flowers are stalkless and a rosy-red colour, about one centimetre in diameter. The leaf rosette at the base of the plant is green, a feature that distinguishes it from some other members of the pink family, which have grey-green leaves.
The plant was given its English name by the 17th century herbalist Thomas Johnson in a celebrated case of mistaken identity. In fact, what Johnson found and described in 1633 was probably maiden pink Dianthus deltoides. As the first name given to a plant is generally the one botanists stick to, the East End of London is 'famous' for a species that has not grown there in historical times, and possibly not at all.
This biennial species flowers in July and August, and is an incredibly prolific seed producer. Each plant can shed up to 400 seeds, although it is thought to need open ground for these to germinate successfully. Once established, the plant can cope with competition from taller species. Seeds disperse in late summer and a rosette of leaves grows the following year. The plant finally flowers the year after that.
This species is fairly common across most of western and central Europe. However, in the UK it is rare and declining faster than almost any other British plant. Once widespread, by 1970 it was reduced to 34 known sites and this figure was down to 15 sites by 1998. These sites are mostly in the south-east of England. The latest survey results revealed that at the end of the 1990s, the plant was found on 34 sites in England and Wales, although at most sites numbers were small.
Deptford pink is a plant of disturbed ground such as tracks, field edges and hedgerows, and dry pasture. It prefers light, dry, sandy soil with a high pH, indicating alkaline conditions. However, it has been found growing at Woodwalton Fen in Cambridgeshire, on quite acid, peaty soil.
The main factors in the disappearance of the Deptford pink are the loss of pasture and the destruction of hedgerows. Many of the meadows where it formerly grew have been converted to arable or turned into building land. The reduction in grazing has also contributed to the scarcity of this attractive plant.
The Deptford pink is listed under the UK Biodiversity Action Plans and included in English Nature’s Species Recovery Programme. It is also part of Plantlife’s ‘Back from the Brink’ project.
The most urgent tasks to preserve this plant are to maintain its current range and manage viable populations on all the present sites. Plantlife and English Nature’s report on Deptford pink for the year 2000 recommended active management of the surviving sites to prevent over-grazing by rabbits and shading out by other plants. Seed has been collected and stored at the Millennium Seed Bank at Wakehurst Place, part of the Royal Botanic Gardens, Kew. This seed may be used for ex-situ propagation and a reintroduction programme if this becomes necessary.
New sites are being discovered each year but all are vulnerable to development or accidental damage. There seems to be a buried seed bank which, following disturbance, produces new plants. Habitat restoration projects may stimulate this seed bank to germinate but it is easy to become complacent. The plant is still very uncommon and could still be lost as a British species.
It is also important that the Deptford pink’s plight is publicised, along with many other farmland plants in danger of disappearing through intensive agricultural practice. These other plants include interrupted brome, cornflower and purple ramping fumitory.
The UK Biodiversity Action Plan for this species is available at UK BAP.
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