I recently purchased a Red Oxalis (aka Shamrock or Woodsorrel) to add to the collection of beautiful weeds I have around the house. Large deep purple shamrock leaves with delicate pink blooms – both of which close every evening and reopen fully in the morning.

Oxalis in bloom

For my own future reference:
Bright Light. Let soil dry between waterings. Cool temps (60-70°), especially when blooming. Requires 2-3 months dormancy (dark and cool) after every major blooming cycle. Tubers can be separated or repotted after dormant period.

Oxalis in bloom