While there are many plants that thrive in full sunlight, containers do not suit all of them. For the best effect, mix plants of different heights and complementing colors. Add a vinca vine to trail over the edge of the box. Supertunias, a compact type of petunia, are colorful flowers that produce long-lasting blooms. Ivy geraniums are available in many colors, produce blooms from June to October and have trailing growth that works nicely in a deck box. Scaevola, also commonly referred to as fan flower, grows to a height of about 6 inches and produces blue, mauve or lavender blooms from mid-spring until fall.
Choose plants that thrive in partial sunlight if your deck box sits in an area that receives sun only part of the day. Try planting lysimachia in the creeping Jenny variety near the front edge of the box, as it produces trailing vines and bright yellow blooms. Lemon Symphony osteospermums are easy to maintain, grow to a height of 8 to 12 inches and produce daisy-like blooms from early spring to fall. Torenias are available in several colors, produce snapdragon-like flowers all growing season and grow to a height of 8 to 16 inches.
For deck boxes in fully shaded locations, select plants that can flourish without being in direct sunlight. Try impatiens, which come in many colors and produce blooms all summer long. A pink splash plant produces beautiful dark green and pink foliage that is easy to maintain and grows well in containers. Begonias are compact, with blooms in a variety of different hues; they grow to a height of 6 to 9 inches. Geraniums are hardy, easy to grow and lend color and a little height to your deck box. Plant some English ivy on the outside edge of the box and it will trail over, adding interest to your arrangement.