The yellow flowers of Dyer’s Greenweed can be seen on the Lizard from June to August. The cliffs near Kynance Farm are a good place to look.
Photo: © Natural England/Neil Pike
Scientific name: Genista tinctoria
Other common names: Dyer’s Broom
What to look for:
- Flowers: Yellow flowers in inflorescences, with typical pea family form of five petals, one erect above, one to each side and two lower petals.
- Leaves: Lanceolate leaves, alternate, with hairs on the margins
- Height: Up to 50 cm, a low shrub
- Where: Grassland and scrub
- When: The flowers appear from June to August.
- Habit: Erect, though may be more prostrate in exposed conditions or when occurring as the subspecies littoralis
- Similar to: Other Whins, such as Petty Whin and Hairy Greenweed, both of which flower a little earlier than Dyer’s Greenweed.
Every name tells a story: Dyer’s Greenweed was used as far back as the fourteenth century to make a cloth dye, and there is evidence it was used earlier, during the ninth to eleventh centuries. It was important to the woollen trade in Kendal in Cumbria, with the colour produced known as Kendal Green, and is even referred to by Shakespeare in his play Henry IV, Part 1.
Dyer’s Greenweed is a relatively common species in England and Wales, possibly with an enhanced distribution due to its cultivation as a dye-plant, but is now declining because it thrives on unimproved grassland, which is also in decline. This impacts on not only the plant, but also the invertebrate populations that depend on it, one of which (Syncopacma vinella – a moth) is now considered extinct.
On the clifftops and maritime heaths of the Lizard you will also find a much rarer subspecies (ssp. littoralis), which is more prostrate in habit, but otherwise shares the bright yellow pea-like flowers and bean-like pods that follow.
Did you know…?
…Dyer’s Greenweed is toxic to humans, but is a larval foodplant of the Green Hairstreak butterfly and a few moths, a small handful of which are restricted to G. tinctoria, and are therefore considered at risk due to the declining distribution of their food plant.
…When used as a dye, the plant first produces, as you would expect, a yellow colour. Dyers then used to dip the dyed fabric into woad or indigo to produce the famous Kendal Green.
More information and references:
Bates, R., and Scolding, B., 2002. Wild Flowers of The Lizard. Cornwall County Council, Cornwall.
Butterfly Conservation, 2013. Dyer’s Greenweed (Genista tinctoria): a Key Plant for Moths and Other Insects (Factsheet). Butterfly Conservation, Wareham, Dorset
Crafer, T., 2005. Foodplant List for the Caterpillars of Britain’s Butterflies and Larger Moths. Atropos Publishing, Holmfirth, UK.
Mabey, R., 1997. Flora Britannica. Chatto & Windus, London.
Rose, F. and O’Reilly, C., 2006. The Wild Flower Key, 2nd edition. Frederick Warne, London.
Stace, C., 2010. New Flora of the British Isles, 3rd edition. Cambridge University Press, Cambridge.
Published: July 2014
Author: Amanda Scott
Photos: Upper: © Natural England/Neil Pike; lower: © Natural England/Peter Wakely