Sour grass, a common plant found in many regions, often prompts questions about its edibility. Known scientifically as Oxalis pes-caprae, this ubiquitous green frequently appears in gardens, lawns, and disturbed areas, leading many to wonder if it can be safely consumed.
Identifying Sour Grass
Accurate identification of sour grass, primarily Oxalis pes-caprae, is important before consumption. This herbaceous perennial is recognized by its distinctive trifoliate, or three-part, leaves, which resemble clover but are typically heart-shaped and may fold at night or when touched. It produces small, five-petaled flowers, most commonly bright yellow, arranged in umbrella-like clusters on separate stalks from the leaves. These characteristics help distinguish it from other plants, including true clovers.
Shoots emerge from underground bulbs, which can produce numerous smaller bulblets annually, contributing to its widespread presence. While the yellow-flowered variety is common, some Oxalis species can also have pinkish or white flowers, but the heart-shaped leaves remain a consistent identifier.
Is It Edible and What Does It Taste Like?
Sour grass is indeed edible, with various parts, including leaves, stems, flowers, and underground bulbs, traditionally eaten. Its most notable characteristic is a distinctively tart or lemony flavor, which is why it’s also commonly called “lemon clover” or “sour clover.” This tangy taste is attributed to the presence of oxalic acid within the plant.
Many find the flavor refreshing, comparing it to citrus fruits like lemon or lime. The intensity of the flavor can vary, but it generally provides a zesty addition to dishes. The leaves and flowers are often consumed raw, offering a pleasant, sharp taste. Even the root bulbs, though less commonly consumed, can be succulent and mildly sweet.
Understanding the Risks of Consumption
While sour grass is edible, its consumption comes with important considerations due to its oxalic acid content. Oxalic acid, which gives the plant its characteristic sour taste, can bind with calcium, potentially affecting nutrient absorption and, in excessive amounts, leading to the formation of calcium oxalate kidney stones in susceptible individuals. This compound is also found in other common foods such as spinach, chard, beets, and rhubarb.
Individuals with pre-existing conditions like kidney issues, gout, arthritis, or those prone to kidney stone formation should exercise particular caution and limit their intake. While minor consumption is generally considered harmless, overindulgence could lead to digestive upset or other adverse effects. As with other foods containing oxalic acid, it is prudent to consume sour grass in moderation as part of a varied diet.
Ways to Enjoy Sour Grass
Sour grass offers several culinary applications that highlight its unique flavor while promoting moderate consumption. Its tart, lemony taste makes it an an excellent addition to fresh salads, providing a zesty and refreshing component. The leaves and flowers can be tossed directly into green salads or fruit salads for an added tang and visual appeal.
Sour grass can also be used to flavor beverages, such as making a zesty lemonade or a herbal tea by steeping the leaves in hot water. Some culinary traditions incorporate it into more complex dishes, like pestos, soups, or even as a stuffing for fish. In South Africa, where Oxalis pes-caprae is indigenous, it is a traditional ingredient in dishes like waterblommetjiebredie, a type of stew. Using sour grass as a flavoring agent rather than a primary food source is the recommended approach, ensuring its enjoyment without excessive intake of oxalic acid.