Most summer bulbs are tropical or sub-tropical plants. Here in our latitudes, they are planted once the weather warms up. They spring quickly to life and produce long-lasting flowers or dramatic foliage -- or both -- from early summer until the first frost. Even in areas where the winters are cold and long, summer bulbs can be expected to put on an impressive show.
Summer bulbs are especially well-known for their leafy exuberance, and elephant’s ears, caladiums, and cannas bring a tropical mood with them wherever they are planted. Victorian gardeners planted cannas as centerpieces in their fancy bedding schemes, but their height also makes them a good choice at the back of a flower bed, either in soldierly rows or grouped shoulder-to-shoulder with tall castor bean plants or elephant’s ears. Hummingbirds will find their flowers very quickly.
Piet Oudolf, the renowned Dutch plantsman and garden designer, many of whose naturalistic plantings are inspired by the beauty and diversity of American’s native prairies, often combines summer bulbs, including lilies of all kinds, with ornamental grasses in strikingly original perennial beds. In 10-foot deep flowerbeds at the New York Botanical Garden, Oudolf mixed lilies with purple coneflowers to dramatic effect. He also plants dahlias and gladiolus with fall-blooming sedum, Japanese anemones, and the bottle-brush blooms of fountain grass. His choices are unexpected, and the effects are surprisingly elegant.
Summer bulbs can be planted in spring as soon as it's comfortable to be out in the garden in shirtsleeves. Most need a sunny spot (caladiums and calla lilies are exceptions), but they are not particular about soil, as long as it drains well. If you’re not sure where to place them, plant a row of summer bulbs in the vegetable garden, and harvest the blooms for bouquets all summer long.