At the flower show all kinds of blooms blazed in rich colors, dazzling to the eye.
Tips
history
From Tang Xianzu's 牡丹亭·惊梦 (Ming opera 'Peony Pavilion'): '原来姹紫嫣红开遍,似这般都付与断井颓垣' - the heroine sees all the brilliant blossoms wasted on a ruined garden. One of the most famous lines in Chinese drama.
usage
Almost exclusively for flowers in full bloom - gardens, parks, spring scenery. Don't use it for clothes or general 'colorful' things; for those, 五颜六色 fits better.