There are more than 50 spring-flowering bulbs that can be planted in the fall. Of course, the most common are tulips, daffodils and crocus. But, there are others such as Pischkinia, Chionodoxa, Allium gigantum, Fritillaria and anemone.

Bulbs are living plants that contain the makings of complete flowers, explains David Robson, University of Illinois Extension horticulture educator. If you slice through a bulb vertically, you might be able to see next year's leaves, stem and flowers. However, most bulbs have to go through a chilling or cold period in order to produce the flower buds.

Spring-flowering bulbs must be planted in the fall in order to take advantage of winter's temperatures. Planting from mid-September through November ensures the 15- to 20-week cooling period necessary for root growth.

Good drainage is essential for all spring-flowering bulbs. If the soil is heavy clay or sand, liberally condition it with organic matter such as peat moss or compost in amounts up to 50 percent of the volume. Fertilization improves bulb performance and encourages bulbs to perennialize. Two fertilizing methods are recommended for spring-flowering bulbs.

The first method uses a sulfur-coated, slow-release, complete fertilizer. The fertilizer—available at garden centers and nurseries—is applied to the rooting area at the rate of 1 rounded tablespoon per square foot at fall planting. Complete fertilizers contain nitrogen, an element that only recently has been found to be beneficial to fall-planted spring bulbs. The nitrogen is absorbed by the bulb and used to produce flowers and leaves next spring.

The second method uses a handful of bone meal applied to each square foot of rooting area, together with an application of 8-8-8 (1 tablespoon) or 10-10-10 (1 heaping teaspoon) per square foot in the fall. Again, it is important that there is nitrogen in the fertilizer.

Make a second application of either fertilizer in the spring when shoots break through the soil surface.

Bulb roots grow down and out, so planting depths and spacing are important. Large bulbs such as tulips and daffodils should be planted 8 inches deep from ground level to the basal plate and 4 to 6 inches apart. Smaller bulbs such as crocus and grape hyacinths should be spaced 4 inches deep and 2 inches apart. The flat bottom of the bulb is the basal plate and the location of new roots.

After planting bulbs, cover halfway with conditioned soil and water thoroughly. Add the remaining soil, and water the area again.

Finally, cover the area with a 3-inch layer of mulch. Wood chips, peat moss or bark are good choices because they do not mat, and they prevent water and nutrients from soaking into the soil.

Several bulb fact sheets can be downloaded from our SI Gardening website, http://web.extension.uiuc.edu/regions/hort. If you don't have internet access, call the Extension office, 439-3178, for a print copy.