The Best Plants & Flowers for Window Boxes

Window boxes are small container gardens. They bring a bit of the country garden to apartment dwellers, decorate suburban homes and extend cottage gardens. The typical window box is 6 to 8 inches deep, limiting the size of flower and plant possibilities, but choices do not have to be confined to petunias and geraniums. Fill your window boxes with flowering plants, bright foliage or create an easy vegetable garden.

Creating a Balance

Window boxes are little works of art. They may complement their surroundings by using a color from their surroundings to set the theme, coordinate with other boxes to form a building-wide picture or they may present stand-alone compositions. Begin with a color theme and find several flowering plants that come in that set of colors; verbena, snapdragons, New Guinea impatiens and dahlias all come in a wide variety of colors. Balance tall plants with trailing vines or trailing forms of geranium or verbena. Fill spaces with dusty miller spengeri or plumose asparagus ferns. Keep plants fresh and blooming by watering daily and grooming regularly; deadhead spent blooms and pinch back shoots to promote bushy growth.

Use the Right Scale

Smaller varieties of many annuals and perennials will grow easily in window boxes. Dwarf zinnias and marigolds create mini cutting gardens. Miniature roses require plenty of sun. Non-stop begonias fill shady boxes with brilliant color. Substitute calibrochoa for petunias; they are smaller, produce more flowers and come in almost as many shades as their leggier cousins. Balance showy canna lilies, exotic Gerber daisies and elegant Martha Washington geraniums with trailing fuschia, mimulus, nasturtiums or sun-loving helichrysum. Use larger plants as specimens; fill the box with flowering herbs like sage, rosemary, oregano, basil or lemon balm. Add contrast with the colorful foliage of coleus, variegated ivies and vinca vine. The National Gardening Association recommends fertilizing flower boxes each week with a quarter-strength solution of water-soluble flowering plant fertilizer.

Salad Days

Vegetables make fine window box residents providing that they are kept well-watered. You may not be able to grow corn in a window box but there are plenty of vegetables that will grow in small spaces. Consider a kitchen window "salad box" of Bibb lettuce, spinach, radishes, parsley and a cherry tomato plant. Interplant endive, arugala, parsley, dill, chervil and Swiss chard for their foliage. Larry Bass, Extension Horticultural specialist at North Carolina State University, suggests that smaller varieties of the following vegetables might be grown in a 5-gallon window box: snap and lima beans, beets, onions and squash. Carrots would require a box at least 1 foot deep. Boxes should have drainage holes to avoid standing water in their bases. Self-watering inserts in window boxes keep roots consistently moist and reduce watering chores.

Keywords: window box, container gardens, plants and flowers, flower box, window vegetable garden

About this Author

Chicago native Laura Reynolds has been writing for 40 years. She attended American University (D.C.), Northern Illinois University and University of Illinois Chicago and has a B.S. in communications (theater). Originally a secondary school communications and history teacher, she's written one book and edited several others. She has 30 years of experience as a local official, including service as a municipal judge.