Why Lobelia Flowers Fade to Pale Blue

Lobelia flowers naturally fade as they age, but new blooms should retain their rich color. If all flowers are pale, the variety may be naturally light blue. In zone 8b, lobelia needs morning sun and afternoon shade — full shade reduces flowering. This cool-season annual declines above 75°F, thriving best in places like Alaska.

Move plants to a spot with a few hours of morning sun. Fertilize with liquid feed after watering, never on dry soil. Hope for cooler weather — lobelia simply doesn't perform well in sustained heat.