Once upon a time, there was a white-flowered member of the Cabbage family (Brassicaceae) called Danish Scurvygrass, Cochlearia danica. It could be found growing on the tops of cliffs, in sand dunes and on sea-walls, and on old walls and between cracks in the pavements of coastal towns. In Norfolk it could be found along the north coast, in the drier parts of salt marshes. It was sometimes found growing on the ballast of railway lines too.
Danish Scurvygrass still occurs in these places but since the 1980s it has spread inland along our road network, as can be seen from this distribution map. In the early days it began to colonise the central reservation of major roads and by 1993 it was established along motorways and trunk roads in 320 ten kilometre squares in the UK. In Norfolk, its distribution now follows the network of ‘A’ Roads and it can be found along many ‘B’ Roads too, such as parts of the B1108 from Norwich to Watton. In Norwich, it lines parts of the ring road and the edges of Farrow Road are a mass of white in April, when the plant is in full flower. The individual plants are small but a continuous mass, knitted together alongside the tarmac, is rather striking.
Main roads are salty places and the recent spread of Danish Scurvygrass is down to its tolerance of salty environments. The movement of traffic probably helps too, spreading its small seeds further along the road network, at a rate that Richard Mabey calculates as 10 – 15 miles per year on some roads (Flora Britannica, 1996).
Danish Scurvygrass is a winter annual, growing through the cold months before flowering in April, setting seed and dying. Its flowers are white but its flowerbuds are pink. Its relative Common Scurvygrass, Cochlearia officinalis, is a perennial and, unlike C. danica, has remained a coastal plant. In Norfolk, it can be found alongside the River Yare and River Waveney, just above where they join Breydon Water, and, more rarely on the North Norfolk coast and in the marshes by the Wash. Common Scurvygrass is normally a larger plant, with a straggly growth habit.
The name Scurvygrass comes from the high levels of Vitamin C to be found in these plants, which will help prevent or treat scurvy. According to the Plants for a Future website, both C. danica and C. officinalis have similar properties and the leaves of both plants are edible. I tried C. officinalis many years ago and I don’t remember it being particularly unpleasant, but the Plants for a Future website says that “very few people will actually enjoy the pungent flavour” of C. danica and that although C. officinalis is “pleasantly sharp”, the flavour is “rather less than pleasant to most tastes”. You have been warned.
In a life or death situation, Scurvygrass would be well worth eating. Common Scurvygrass and the related Cochlearia anglica, C. groenlandica and C. fenestrata are found in Spitsbergen (Andreas Umbreit, “Guide To Spitsbergen”, Bradt Publications 1997) and in his 1905 book “No Man’s Land: A History of Spitsbergen”, Sir Martin Conway recounts how a Dutch whaling party overwintered successfully in 1633-34, partly because they managed to find large quantities of Scurvygrass. In the following year another overwintering party had died of scurvy by the time spring arrived, having not found any of the plant. (The first group also hunted reindeer, and there would also have been Vitamin C in the fresh meat.)
The Wild Flower Finder, Nature Spot and West Highland Flora websites have some very good photographs of Danish Scurvygrass, which also known as Early Scurvygrass. The Wild Flower Finder website also gives more details of some of the chemical compounds found in the plant. The name Cochlearia comes from the Latin word cochlear, meaning ’spoon’ and refers to the shape of the leaves. ‘Scurvygrass’ can also be written as ‘Scurvy-grass’.