What part of the plant does the flower attach to?

Flowers are jointed to the stalk through a structure called the receptacle. This structure carries the floral organs and serves to connect the flower to the rest of the plant once it blooms, according to Andromeda Botanic Gardens.

Many plants use flowers in order to reproduce through the process of pollination. Flowers contain both male and female sex organs, known as gametes, that are responsible for the exchange of pollen necessary to the reproductive process. Both developing floral organs and fully mature blossoms attach to the rest of the plant through a structure known as the receptacle, which serves to join the flower to the peduncle.