Florists often use specially bred flowers that either produce less pollen or have had their stamens removed to prevent pollen from spreading and making a mess, which can also be beneficial for people with allergies. This breeding process involves selecting plants over generations for those that naturally produce less pollen or have less prominent reproductive organs.
Regarding rerooting cut flowers, it's generally difficult, but not impossible with certain species. Most commercially available cut flowers have a low chance of rooting because they are mature and their stems are cut in a way that doesn't promote new root growth. Some, like roses, might root if treated with rooting hormone and provided with the right conditions. However, these rooted plants may not always produce flowers, as the breeding for long stems and large blooms can come at the cost of the plant's ability to reproduce naturally. For cut flowers, the focus is on traits that are visually appealing rather than reproductive capability.
