A flower development stage (PO:0007615) that occurs in an individual flower (PO:000904) during the interval between the onset of a floral organ meristem development stage (PO:0007601) and the onset of a flowering stage (PO:0007616).

During this stage, the process of floral organ development (GO:0048437) occurs. Floral organ development is defined as the process whose specific outcome is the progression of the floral organ over time, from its formation to the mature structure.