Window boxes are often used in urban areas as the only means of gardening since there is little or no other space, according to Carol Spier, author of "Garden Ideas." The houses or buildings are set up against sidewalks and streets. New Orleans' French Quarter is a good example of street-side gardening with window boxes. Make sure the window boxes are securely fastened to the window or building before planting.
Plant a minisalad garden if your window box gets six hours of sun. Stick with leaf variety lettuce instead of head type. Sprinkle the seeds over the soil, and then cover the seeds with 1/8 inch of soil. Harvest the lettuce by cutting individual leaves with scissors rather a whole head.
Small varieties of tomatoes like patio pick will do well in a window box. The plants stay compact. Add some basil, a bush cucumber and a green pepper.
Light up a shady window with bright-colored flowers. Impatiens have small round leaves and flowers the size of a quarter in pinks, purples, orange and white. The plants are nearly covered with flowers once blooming starts. Fuchsia flowers are a combination of purple, bright pink and red. The flowers trail and will obscure the window box completely. Another shady flower are begonias with golf ball size flowers.
Try hostas, coleus and trailing vinca. The leaves come in shades of purple, yellow, orange and pink in the case of coleus. Vinca is green, green edged with white or green edged with yellow. Hostas have a rosette shape. Choose a hosta that stays on the smaller side for a window box.
Cool a sunny window with flowers in tones of white, blues and purples. Plant blue salvia in the back of the box. It grows to 18 inches high. Place white petunias in the center. Edge the box with light purple alyssum to trail over the edge. Fill in with blue lobelia. Keep window boxes in the sun well watered. They dry out quickly.
White flower boxes are stunning if the flowers contrast with the color of the house. White flowers against beige stucco won't go anywhere, while those same flowers against red brick stand out. Try flowering kale with its bicolored white and green ruffled leaves with white bacopa, white miniature roses and white snapdragons. Place the tall snapdragons in the back of the box the roses in the center with a kale on each side. The bacopa will grow over the sides of the box.