The go-to ingredient now when we want to add a sharp, sour note to a dish is the ubiquitous lemon. However, back when lemons were exotic imports, it was only the super rich who could afford to use them regularly. Much more available would have been the patch of Common Sorrel (Rumex acetosa) in the garden. The leaves of this easy to grow plant have a powerful acidity, which is not only a substitute for lemon, but makes a delicious ingredient in its own right.
The name sorrel derives from the French word for sour. The acidity comes from oxalic acid in its leaves and stems, which is perfectly fine in small amounts, but should not be consumed regularly by the basketful, particularly for those with rheumatism, kidney stones or gout. It was often a constituent in medieval ‘verjuice’ – an early substitute for vinegar. The leaves were a much prized sauce ingredient during the time of Henry VIII and to John Evelyn in the 17th century, sorrel added ‘so grateful a quickness to the salad that it should never be left out’
There are a few species of sorrel worth eating. Our two natives that can be found in the wild are common sorrel (Rumex acetosa) and sheep sorrel (Rumex acetosella). As ever, if you are gathering from the wild, be confident of your identification and do not take from sensitive sites. There are a few named varieties of the common sorrel that have been selected for larger leaves, so for your garden it would be worth seeking these. French Sorrel (Rumex scutatus) was introduced towards the end of the 1500s, and soon overtook its English cousin in popularity. They also suit different soils, the common being happy in damp conditions and the French preferring a dry position.
Docks and bloody dock
As a close relative of the docks, it is no surprise to discover that sorrel plants are generally easy to grow and tenacious once established. They put down a deep taproot, so they can survive being cut back hard and will return year after year. If after a few years the clump looks to be getting congested, they can be dug up in winter and split into 4 parts with a spade and then replanted. They will try to flower and set seed each year but I cut these off to concentrate energy on leaf production. They will often stay green through the winter and come into new growth very early in the year so they are great for jazzing up the blander winter leaves. Sorrel is ideal to cook with spinach or chard, shredded raw into a salad, or puréed for sauces or soup.
Another species worth growing is bloody dock, also known as red veined sorrel or bloodwort (Rumex sanguineus). This is excellent as a young leaf though it goes tough very quickly so it’s best sown little and often. As it is harvested so young, it is ideally suited to growing in pots or small troughs on a windowsill with other small salad leaves and the flavour at this stage is more mild tang than acidic punch.
The only pest I have ever encountered on sorrels is the dock beetle. Despite its name, it prefers to feast on the more delicious sorrel (understandable really). They are handsome beetles, with a blue/green iridescent carapace, but will make lacework of your leaves. The only effective action I have ever taken is to cut the plants back right down to the ground after the beetles have laid their eggs, which seems to disrupt their life cycle.
Though nowadays we are all able to access a variety of citrus fruits, the flavour, versatility and all round easy-goingness of the sorrel should ensure it has a place in your garden.