I recently purchased 2 Calla Lilies which are in full bloom (one white and the other deep purple). There were no instructions relating to the care of them apart from a temperature range of 8-22 deg. Having read the info on your site, no reference is made regarding temperature tolerances. I have them in pots in a sunny position in a northwest facing garden in Kent, UK but keep moving them into the shade to avoid the increased temperatures we are currently experiencing (28 deg C.). Could you please clarify this for me?
Your Calla Lilies will enjoy the summer temperatures but you will need to water twice a day when temperatures are about 80 degrees F.
Here is a link to the proper care.