When intended as positive, red stands for inspiration, vitality, beauty, strength, courage, victory and will-power. When in negative context, the color red symbolizes lust, malice, aggression, and anger. All of these themes, both positive and negative, were very present in American Beauty. Without a doubt, the most numerous vessels for the color red was the rose. In almost every scene in the house, there is a tight bouquet of the red roses from Carolyn's front garden.
Roses symbolize love, magic, hope, and passion.
A rose is the physical form of ultimate beauty and perfection. It is delicate and deep, yet surrounded by thorns. Perhaps the rose could symbolize the catalyst character of Angela, who appears to be the perfect specimen of American beauty. Underneath, she has many of her own personal demons, or thorns. The roses could also symbolize the lost beauty in Lester Burnham's life.