The two common docks are among the five official ‘injurious weeds’ in Britan, but curled dock has long-recognised redeeming qualities as a detoxifying liver and bowel herb, a laxative and a blood cleanser. The root is effective for many chronic toxic skin conditions, including acne and boils, eczema and sunburn, not forgetting the most famous use of dock leaves for relieving the burning caused by nettle stings.
Polygonaceae Dock family
Description: A perennial dock growing to a metre tall. Leaves are long and parallel-sided with wavy margins; tap roots have a brown outer covering and are yellow within.
Habitat: Grassland, disturbed ground, farmyards, road verges, river banks, coastal shingle and mud.
Distribution: Common throughout the British Isles, and native to Europe and Africa, curled dock is one of the most widely distributed plants in the world.
Related species: The other widely distributed species is common or broad-leaved dock (R. obtusifolius), with which yellow dock will hybridise. Broad-leaved dock can be used interchangeably with curled dock – the thing to look for is a yellow root in either species, which indicates the presence of the medicinal compounds.
Parts used: Root, dug up in autumn (provided it is yellow, use any species); leaves.
We have included dock in this book even though it is the root that is most used, as it is such a common weed across the world. Found in almost every field, garden and lawn, it is likely you have some growing on your own plot that you can dig up for medicine.
Dock’s tap roots are long, slender and deep, going half a metre down; any stray piece left in the soil can sprout into a new plant. Each dock can produce 30,000 or more seeds a year, and these can lay dormant for up to fifty years. It is no wonder it is hard to eliminate. In addition, curled dock and common or broad-leaved dock hybridise freely. It is an almost unstoppable weed, yet one with redeeming medicinal benefits.
Dock’s botanical success is official: both common British species are classed as injurious weeds in the Weeds Act 1959 (along with common ragwort, spear thistle and creeping or field thistle). The Act stipulates that farmers should take steps to prevent the spread of these five weeds: a scene like the one opposite of a fallow field filled with autumnal curled dock ought to be harder to find than it still is.
Use curled dock for…
The one thing everybody knows about dock is that you rub its leaves on the skin when stung by nettle. This practice goes back centuries, being mentioned in the Anglo-Saxon leech-books and in Chaucer’s Troilus and Criseyde, suggesting docks have always been freely available. Formerly, a chant was sung when applying the dock: in Ireland, it might be ‘docken, docken, cure nettle’; in Cornwall, it was along the lines of ‘dock leaf, dock leaf, you go in; sting nettle, sting nettle, you come out’.
It is a cooling and astringent treatment, especially the sizeable leaves of broad-leaved dock, although we prefer treating nettle rash by plantain leaves. Digging up a few dock roots, pulping them and applying as a poultice, and renewing this every few hours, is another old nettle standby, as is a root tea. In South Africa, Tswana women warm up dock leaves and apply them to swollen breasts during lactation; they also use the root pulp to treat piles.
Ripening curled dock: a pink bonnet for each seed
Curled dock, by Maria Merian (1717)
One Anglo-Saxon recipe for reducing a groin swelling (attention, you footballers!) was to pulp dock leaves in grease, wrap in a cabbage leaf that had been warmed in hot ashes, and apply as a plaster. Culpeper (1653) suggested boiling roots in vinegar for bathing itches, scabs and ‘breaking out of the skin’. Modern external uses have added chronic acne, boils, bites, cuts, sunburn, easing rheumatic aches and soothing inflamed gums (using a powder of dried roots).
The reputation of dock as a ‘blood cleanser’ is also ancient, being known in Chinese medicine, Indian Ayurveda and in classical Greece, whence comes dock’s old family name ‘lapathum’ or blood purifier. It was found that dock transmutes iron in the soil to organic iron in the plant (a real case of alchemy!); old herbalists would add iron filings to soil near dock to ‘enrich’ it. This property makes dock effective for iron-deficiency anaemia and for period problems, especially in younger women.
Dock also has a laxative effect in which it stimulates gut motions; indeed it was once used as a purgative. It is a good natural remedy for constipation, reflux and acid stomach, and has been called a ‘superlative remedy’ for enteritis, colitis, diarrhoea and dysentery.
Dock’s twin qualities to cleanse and to lower heat make it an ideal liver detox treatment, including for jaundice and ‘liver stagnation’, when the flow of bile is congested, and for disorders of the spleen and lymph. A healthy liver means a healthy skin, and dock works on both; the advice is to use small quantities over a long period.
Dock root gives a gluten-free flour, once a famine food. The young leaves of curled dock cook as a tasty spring vegetable with a light lemony taste, and are good in nettle soup. Avoid too much raw dock, though, as it contains oxalic acid, which is toxic in quantity.
Harvesting dock
Dig up the roots in late summer or autumn. Large older plants are more likely to have a strong yellow colour to their roots. Scrub them well, and cut off the tops.
Curled dock tincture
Fill a jar with chopped-up dock roots. Pour vodka in until the roots are covered and put the lid on tightly. Keep in a cool dark place for a month, ideally shaking the jar every day or two.
Strain off, using a press or squeezing through a jelly bag. Bottle the liquid, remembering to label it. This tincture will keep for about five years in a cool dark place.
Dose: Half a teaspoonful once or twice daily as a cleansing tonic.
Take when the bowels are sluggish, for anaemia and poor absorption of nutrients (if the edge of your tongue shows scalloping from your teeth), for skin problems and any time you feel a bit slow and tired.
Curled dock root in cross-section, showing the yellow colour
The wavy leaf edge (and typical snail hole) of curled dock