My pansies have floppy petals... is that normal? How can I make them to be less floppy?

I have planted some Giant Majestic Pansies in a window box. They are in a pretty well sun area... they get approx. 5 hrs of sun every morning. I water when soil is dry and it is well fertilized. The plants are giving plenty of flowers, but they petals of the flowers are very floppy... It's that normal for the Giant Majestic pansies? How can I make them have more stable petals??

My pansies have floppy petals... is that normal? How can I make them to be less floppy?
Well you are looking after these pansies perfectley but the truth is this is normel leave the flowers do not dead head and let the flower heads go to seed and plant them next year.