I have watered my new plants every day during that week of 100 degree weather. Now not so often. The established plants I have watered about every other week during the dry spell. As I sit here typing, a storm has just passed. It was a pretty heavy rain, not sure how much, but for once I won't have to be watering today! We've had some rain each week for the last three. It's not soon enough to help the farmers corn crop I fear, but maybe there will be a 3rd crop of hay, and the pastures might come back some for fall grazing if this keeps up. I remember the first year that I had irises. I think I watered every other day or so. I have no idea why I didn't kill them all, other then I have very sandy soil here, and that must have saved them.