Genus of about 500 species of fibrous-rooted, bulbous, rhizomatous, or tuberous annuals and perennials, from various habitats worldwide. Some types of oxalis have shamrock-like leaves. Most require full sun and an evenly moist soil when actively growing. Dormant plants are kept drier. Use dilute liquid fertilizer, at weekly intervals on actively growing plants. Bulbous types are planted in autumn. Plant the bulb 1/2 inch deep and place the pot in a dark area until growth appears. When growing, move it to its regular growing area. Oxalis deppei has red flowers in spring, Oxalis cernua (Bermuda Buttercup) bears yellow blooms and Oxalis Bowiei is pale purple. The leaves close at night.