Flowering bulbs offer a multitude of opportunities to enhance your landscape aesthetics. With ranges of color, bloom type, and size, as well as their long sequence of bloom, bulbs are unequaled in any other class of flowers. Purdue’s Michael Dana, Paul Pecknold, and Cliff Sadof co-authored a publication on flowering bulbs, from which we’ll glean a few blooms of knowledge today.
“Bulbs require little garden area and can be planted in annual or perennial flower beds, among shrubs, under trees, and in practically every area of the landscape,” they said. “By careful scheduling, a gardener can have flowering bulbs in bloom before the last snows in spring until the first snow in the fall.”
The experts explained that bulbs are considered either hardy or tender.
Hardy bulbs survive winters in the ground and may be left in place all year. Most of them should be planted in the early fall. However, lilies, which bloom in early to midsummer, may be planted in fall or early spring. Examples of hardy bulbs include crocuses, daffodils, tulips, hyacinths, and grape hyacinths.
Tender bulbs must be lifted after the growing season, stored indoors, and replanted the following year. Store in a cool, dry location. Do not store in plastic bags, as accumulated moisture may cause mold. They should be planted outdoors in spring only after the danger of frost is past, or they may be started indoors for later transplanting. Examples of tender bulbs include dahlias, cannas, tuberous begonias, and gladiolus.
“The best bulbs come from reputable businesses, either local or catalog sources,” they said. “Select large, firm, plump bulbs or roots.” The experts warned against purchasing any bulbs that are bruised, blemished or soft.
“The most important environmental factor to consider in locating bulb plantings in the landscape is light level,” they said. “Be sure you provide full sun or partial shade as the particular species requires.”
“Nothing will cause bulbs to deteriorate as quickly as poorly drained soil,” they said. “Most bulbs prefer a well-drained, sandy loam soil, ideally with moderate amounts of organic matter.” If the subsoil is highly impervious to water, they recommended some disruption by deep digging or raising the bed level to 2-3 inches above the average surrounding soil.
“The size of the bulb, plant and flower controls spacing; thus, small bulbs are planted more closely together than larger bulbs,” they said.
Plant bulbs with a trowel or a bulb planter. “A trowel is preferred since it avoids compacting the soil immediately below the bulb,” they said. “For larger bulbs, use a trowel or spade to make the larger holes.”
They said that correct planting depth is important. “Generally, plant at a depth equal to 2-1/2 to 3 times the bulb’s largest diameter,” they said.
For hardy bulbs, they said an annual application of fertilizer as a top dressing is needed as foliage growth begins in the spring. Apply at the manufacturer’s recommended rates.
“Foliage of bulbous plants must not be cut until it begins to yellow and die,” they said. “Leaves furnish food to the bulb, permitting it to grow large enough to flower the following year.”
For additional information, search for the referenced publication, “Flowering Bulbs,” at The Education Store, www.edustore.purdue.edu.