Oxalis versicolor - aha!
Diane Whitehead (Thu, 11 Dec 2003 14:30:12 PST)

I have been waiting weeks for my pot of Oxalis versicolor to open its
buds. On the infrequent days that the sun shines into my attached
greenhouse, I make sure the pot is being shone upon. All to no
avail. Not a single flower has opened.

Today is one of our common gray days - the weather report gave a
promise of sunny breaks, but the fog hasn't burned off yet. I
decided to try something different, so I brought the pot into the
warm living room. Guess what? Yes, half of the flowers are open.
So it is heat they want, not sun.

The greenhouse maintains itself during winter between 5 and 10
degrees celsius. (about 40 to 50 degrees Fahrenheit). My living
room is heated to 18C (about 65F). I should walk my pot of oxalis
around the cooler parts of the house to see what its precise
requirement is for opening.

--
Diane Whitehead Victoria, British Columbia, Canada
maritime zone 8
cool mediterranean climate (dry summer, rainy winter - 68 cm annually)
sandy soil