HO-86
Flowering Bulbs

HOME YARD & GARDEN • DEPARTMENT OF HORTICULTURE
PURDUE UNIVERSITY COOPERATIVE EXTENSION SERVICE • WEST LAFAYETTE, IN
Ruth Kvaalen and Michael Dana, with
Donald Schuder and Robert Corrigan, Entomology,
and Paul Pecknold, Botany and Plant Pathology

Flowering bulbs offer a multitude of opportunities for brightening the home landscape. Their range of color and bloom type and size, as well as their long sequence of bloom, are unequalled in any other class of flowers. Although most gardeners think of lilies, tulips, hyacinths, and narcissus whenever the term "bulb" is mentioned, there is an almost unending array of bulbs.
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. By careful scheduling, a gardener can have flowering bulbs in bloom before the last snows in spring until the first snow in the fall. Besides variation in cost, bulbs’ permanence and rate of multiplication should also be considered when planning a garden.
This publication discusses when to plant bulbs and explains soil preparation methods and planting procedures. Also provided is a convenient table including information on various bulbs’ characteristics and requirements (Table 1). To simplify access to the table, an Index of Common Names is also provided. The term "bulb" is used in this publication to refer also to all corms, tubers, and rhizomes handled in the dormant condition.

Bulb Hardiness Dictates Planting Time
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 early in the fall. Proper planting time is important not only for winter survival, but to insure adequate root development, which results in better flower production. Tender bulbs must be lifted after the growing season, stored indoors, and replanted the following year. See HO-85 for information on storage of tender
bulbs. Tender bulbs should be planted outdoors in spring only after all danger of frost is past, or they may be started indoors for later transplanting.
Hardy flowering bulbs forced in a pot for indoor, winter bloom may be planted permanently in the garden. However, such bulbs seldom bloom well the first year after planting out. If they grow at all, they may take several years to flower again. They should be moved outdoors in spring after frost danger is past. Plant the entire contents of the pot.
While indoors, these plants should be placed in a well-lighted location and fertilized like any other indoor house plant. Be sure to allow the foliage to remain green until it naturally dies back (usually 5 to 6 weeks after flowering).

Buying Bulbs
The best bulbs come from reputable businesses, either local or catalog sources. Order bulbs early from catalogs, and make your selections at local sources as soon as the bulbs are offered for sale. Select large, firm, plump bulbs or roots. Do not purchase any that are bruised, blemished, or soft.
During their dormant season, tulip, narcissus, and most other bulbs with a protective covering of dry scales can be stored for several weeks prior to planting, if necessary. Some, such as fritillaria and snowdrops, deteriorate rapidly and should be replanted as soon as possible. Similarly, fleshy bulbs and roots like lilies should be planted immediately after purchase or delivery.

Using Bulbs in the Landscape
The most important environmental factor to consider in locating bulb plantings in the landscape is light level. Be sure you provide full sun or partial shade as the particular species requires (Table 1). Excellent soil drainage is also crucial for most species, but poor condi-