Exploring the light source spectral characteristics to enhance the perceived attractiveness of natural flowers

The visual appeal of flowers in retail and aesthetic settings is significantly influenced by lighting. Although previous research has examined how different light sources impact flower colour perception, the effect of specific colour rendering metrics remains underexplored. This study conducted a visual experiment to identify the optimal spectrum for presenting natural flowers more attractively. Ten illuminants with a correlated colour temperature around 3500 K were selected using k -means clustering and generated using a multi-channel tuneable light source. Between 6 and 14 observers participated in a paired comparison visual experiment. Results suggest a positive correlation between the ANSI/IES TM 30-24 (TM-30) local chroma shift ( R csh, j ) and the visual attractiveness of red and green flowers. No significant correlation was observed with the TM-30 colour fidelity index ( R f ), gamut area index ( R g ), the CIE colour rendering index (CRI R a ) or memory colour rendering index. The most attractive spectra for red flowers exhibited high R csh,1 , whereas the most attractive spectra for green plants exhibited high R csh,6 . A spectrum with high values of both R csh,1 and R csh,6 was identified as optimal for enhancing the visual attractiveness of red flowers and green plants. However, no optimal spectrum was found for yellow flowers.