Lobelia trails and cascades from baskets and window boxes with fine-textured stems and tiny flowers—the kind of airy softness that fills gaps between bolder plants. Sold in spring through early summer as small rooted plants ready to grow out fast once you set them in decent light.

Full sun to part shade works fine; regular water keeps them happy in heat. Deadhead spent flowers or just let them sprawl loose and refill themselves all season long.