I have grown bergonias from corms planted out now in various baskets and boxes they now look very strong with lots of leaves but not a flower in sight they are illumination orange I am new to gardening and bought the corms from mirror website don't know if I bought from correct place or whether that's relevant they seemed to struggle when first in greenhouse took a long time to grow may be cold weather earlier in year but as great as they look now no flowers can any one help or may be I need more patience. Dave Marsh.
Make sure you are not over fertilizing. Too much nitrogen will inhibit flowering.
This link will refresh you on the care requirements.