Least Yellow Sorrel, Shady woodsorrel
Oxalis exilis
Family: Oxalidaceae
What it is like
Oxalis exilis is a ANNUAL/PERENNIAL growing to 0.1 m (0ft 4in) by 0.3 m (1ft). See above for USDA hardiness. It is hardy to UK zone 5 and is not frost tender. It is in flower from June to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. The plant is self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil.
Height (m): 0.1
Where it is found
Arable land and waste places, it is a common garden weed where it tends to become especially troublesome in pots of plants growing in greenhouses etc.
New Zealand and Tasmania.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Leaves - raw or cooked. Added to salads, cooked as a potherb with other milder flavoured greens or used to give a sour flavour to other foods. The leaves are available all year round unless the winter is very cold, they have a pleasantly sour taste, but are very small and fiddly to harvest. The leaves contain about 86% water, 2.3% protein, 0.8% fat, 8.2% carbohydrate, 150mg calcium, 78mg phosphorus, 8mg iron, 0.6mg niacin, 78mg vitamin C, 6050µg beta carotene. The leaves contain between 7 - 12% oxalate. Use in moderation, see notes at top of sheet, Flowers - raw. A nice acid flavour and a pleasant addition to the salad bowl.
Medicine
Rating: 2
The whole plant is anthelmintic, antiphlogistic, astringent, depurative, diuretic, emmenagogue, febrifuge, lithontripic, stomachic and styptic. It is used in the treatment of influenza, fever, urinary tract infections, enteritis, diarrhoea, traumatic injuries, sprains and poisonous snake bites. An infusion can be used as a wash to rid children of hookworms. The plant is a good source of vitamin C and is used as an antiscorbutic in the treatment of scurvy. The leaves are used as an antidote to poisoning by the seeds of Datura spp, arsenic and mercury. The leaf juice is applied to insect bites, burns and skin eruptions. It has an antibacterial activity.
Urinary: Treats urinary problems, including urinary tract infection (UTI).
Vitamin C: Plants good for their vitamin C content
Other
Rating:
How it is grown
A very easily grown plant, succeeding in a sandy soil in a warm dry position. It prefers dry open habitats. Spreading rapidly by seed and underground bulbils, this species can quickly become a nuisance, it is a common weed of pot plants in nurseries.
Propagating it: Seed - best sown as soon as ripe in a cold frame. This plant does not need any encouragement.
Best place to grow: Cultivated Beds;
Habit: Annual/Perennial
Hardiness: 4-8
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: No shade
Moisture: Dry, moist
Things to keep in mind
The leaves contain oxalic acid, which gives them their sharp flavour. Perfectly all right in small quantities, the leaves should not be eaten in large amounts since oxalic acid can bind up the body's supply of calcium leading to nutritional deficiency. The quantity of oxalic acid will be reduced if the leaves are cooked. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition.