A year and a half ago I changed the configuration of my vestibule greenhouse so that one planting bed was kept covered, the overhead pane no longer being removed for the summer. In addition, I ceased watering it. A few plants were left behind, out of inertia if nothing else: Acis nicaensis, Oxalis melanosticta, and O. triangularis. They not only survived the new regime, they thrived; in fact the Acis in particular did better than it had when pampered. As a bonus, O. melanosticta appears in winter, O. triangularis in summer. The space experiences a minimum temperature of 15oF (-10oC), which is quite comfortable for all the plants concerned. Jim Jones Lexington, MA