Choosing tall garden plants can be an inexpensive way to hide an electrical box. Annual sunflowers are easy to grow from seed and come in a variety of colors, including yellow, bronze, rust and cream. Hollyhocks are best started from small plants for faster growth. By mid-summer, their 5- to 7-foot-tall spikes will be covered with flowers. Hollyhocks are a perennial plant, so they’ll come back next year.
Use vines to create a more permanent screen. Since you’ll want to make sure the electrical box is accessible, you should train any vine on a trellis. Install the trellis so that the vine will grow to the side, then you can train shoots around the box to eventually hide it, but not completely cover it. Clematis vines are a favorite choice, with their lush summer growth and purple, lavender, pink or white flowers. In colder areas, they’ll die back to the ground in winter, so roots should be mulched for protection. Climbing roses come in a wide variety of colors and grow very quickly. They’ll require a little more pruning and care, but their colorful blooms in summer will be worth it.
Planting a tall shrub or tree may be a bit more expensive at the outset, but once planted, most will require minimal care and camouflage throughout the year. There are many varieties of viburnum shrubs, from dwarf varieties that grow to 3 feet to others that grow as high as 20 feet. Sky pencil holly trees are wonderfully compact and can be planted as a screen. They will grow quickly, reaching 10 feet high.
For areas that have problem soils, tall ornamental grasses are easy to grow and maintain. Grasses require full sun and can survive a dry summer. Dwarf pampas grass will grow to 6 feet tall, with showy, fluffy seed heads in late summer. Broadleaf bamboo is a tall (8 to 10 feet) screen that is also a perennial. When planting grasses and bamboo plants, sink a metal tub in the ground and plant the roots inside the tub to keep the roots contained. Grasses and bamboos are notorious for spreading and can be difficult to control once they do.