I put my six strelitzia on the back porch. They only get sun for the first and the last few hours of the day and they are kept well watered. Their leaves are now curling into the form of a tube. I would attribute this to lack of water (curling to reduce respiration) or excess heat/sunlight (curling to avoid the sun). But it can't be either of those. Any suggestions? I can post pictures - but only once our camera is fixed.