"Beginning gardeners may not be familiar with the light levels or soil conditions of their garden plots," says residential landscape designer Kim Kaulas, of Chicago (kimkaulas.com). To meet that challenge, her vote goes to the wax begonia, with its glossy, succulent leaves in green, bronze or red, and its tidy mound of flowers.

"They take a wide range of light levels and can handle wet-to-dry conditions," she says. The plants are annuals: Plant them after all threat of frost has disappeared (in our growing Zone 5, this usually is mid- to late May, but if you're unsure, ask an expert at a garden center) and they will last until the first hard frost in autumn, typically sometime in October. Wax begonias are usually sold in "flats" of six or more plants. "They come in various flower and foliage color combinations, they'll take full sun or full shade, they're drought-tolerant and they don't require deadheading," Kaulas says.