Which factor does NOT affect the longevity of cut flowers?

The longevity of cut flowers is primarily influenced by factors that relate to their environment and care. Lighting conditions and temperature are crucial because they can accelerate or inhibit the flower's natural processes, including respiration and water uptake. Additionally, water quality and temperature are vital since impurities in water and unsuitable temperatures can lead to bacterial growth or reduced absorption by the stems, both of which can shorten the flowers’ life span. Floral preservatives are specifically formulated to enhance the longevity of cut flowers by providing essential nutrients and controlling bacteria.

The arrangement style and aesthetics, while important for the visual appeal of floral designs, do not play a direct role in the longevity of the flowers themselves. This factor focuses more on the presentation and artistic aspects rather than the biological needs of the flowers. Thus, it is the factor that does not influence how long the cut flowers will last after being arranged.