Q.Canna Lilies In Tunisia. The Flowers Shriveled Up
My canna lilies seemed very healthy last summer. I grew them from new rhizomes in large pots as I have a 2nd floor terrace sheltered by the house and 3 sides of 4ft walls. I kept them fed and watered. They were in full sun last summer but when the flowers came they just dried up after one day. I do not have photos

Certified GKH Gardening Expert
Was the soil kept consistently moist? Have you inspected the leaves and buds for insects? Were the plants in full sun 4 to 6 hours a day? The more sun, the better they will bloom. Canna lilies will sacrifice blooms if they are not getting enough water or nutrients. Here is more on their care:
https://www.gardeningknowhow.com/ornamental/bulbs/canna/canna-lily-fertilization-tips.htm
https://www.gardeningknowhow.com/ornamental/bulbs/canna/managing-canna-lily-pests.htm
https://www.gardeningknowhow.com/ornamental/bulbs/canna/canna-lily-care.htm
https://www.gardeningknowhow.com/ornamental/bulbs/canna/deadheading-canna-lily-plants.htm