Oxalis gigantea

This Oxalis comes from an area in Chile with scarce winter rainfall, dry summers and abundant humidity in the air. It is a shrub, 1-2 m tall and ocasionally more, with succulent trifoliate leaves and abundant bright yellow flowers. Oxalis gigantea is the largest species in the genus. It is slow growing and long leaved.

It grows new leaves and sheds them whenever conditions are favourable, and this can happen more than once a year. In habitat it is leafless for most of the year, especially in the heat of summer. 

Pictures from wikimedia commons:
By Stan Shebs, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3699064
By Stan Shebs, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3852723