Oxalis

Oxalis or wood sorrels are small bulbous and perennial plants from the Oxalidaceae family, most often creeping, whose leaves resemble those of clover. They are appreciated for their long spring or even summer flowering, ranging from white (Oxalis deppei 'Alba') to yellow and purple, as well as curiously striped with red and white in the case of the Oxalis versicolor. The flowers are formed of five cup-shaped petals. Some, like Oxalis triangularis, offer decorative purple foliage as well as its pink flowers. Oxalis can be recognized by their leaves, which are divided into three heart-shaped leaflets that open during the day and fold up at night. Oxalis plants are more or less hardy depending on the species (from -3 to -15°C (26.6 to 5°F)), but they can be easily cultivated in pots indoors. In favorable climates, some Oxalis species can become invasive.