Colorful foliage plants add a bright touch to any garden or patio. Plants with purple and green leaves lend a unifying feel. The color combination is an excellent backdrop to showcase more colorful flowers, and it provides color during periods when other plants are not blooming. Plants that form mounds of purple and green leaves create an artistic segue from one area of landscaping to another. Use purple and green foliage plants in containers as special accents.
Persian Shield (Stobilianthes dyeranus)
Persian shield plants grow in full sun or light shade. The plants are tall, growing to a height of 3 feet. Pinch back the plants to control the size, and to encourage branching and bushiness. Unpinched plants tend to get leggy. The silvery-green and magenta leaves grow to 8 inches long; they develop a metallic sheen. Persian shield grows readily from cuttings. Bring it indoors in the winter to enjoy it as a houseplant.
Ornamental Sweet Potato (Ipomoea batatas)
Low growing, trailing sweet potato plants make an ideal ground cover or filler plant. Planted in containers, ornamental sweet potato vines trail over the sides. The plants cover a 2- to 5-foot area with heart-shaped leaves. Ornamental sweet potatoes are fast growing, and they will carpet an area with color that may be anywhere from chartreuse to deep maroon. The plants are not cold hardy. Dig the tubers in the fall, and store them where they will not freeze.
Wood Sorrel (Oxalis purpurea)
Grown from small bulbs, this variety of wood sorrel has leaves with green above and purple beneath. The flowers may be rose, pink, violet or white, measuring 1 to 2 inches in diameter. In climates without freezing temperatures, the plants multiply by runners and bulblets, forming colonies. Northern gardeners grow wood sorrel in containers and window boxes, and store the bulbs in a protected place over the winter.
Moses in the Cradle, Purple-Leaves Spiderwort (Rhoeo spathacea)
The strappy leaves of Moses in the cradle grow from a central whorl, making it a candidate for pot planting. This spreading plant reaches 12 to 18 inches in height, with leaves that drape over the sides of a pot. The leaves are dark green, with a purple metallic tinge on top and deeper purple underneath.