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Extension Communications
3614 Administrative Services Building
Ames, Iowa 50011-3614
(515) 294-9915

9/28/98

Contacts:
Cindy Haynes, Extension Horticulture, (515) 294-2751
Elaine Edwards, Extension Communications Systems, (515) 294-5168

Yard and Garden Column for the Week Beginning Oct. 2.

SELECTING AND PLANTING SPRING-FLOWERING BULBS

By Cindy Haynes
Extension horticulturist
Iowa State University Extension

As the garden season winds down for the year, now is a great time to select and plant a few spring-flowering bulbs for next year. Spring-flowering bulbs offer reliable color and fragrance to the garden before many other plants wake from their long winter's nap. Gardeners can choose from traditional spring-flowering bulbs, such daffodils, tulips and hyacinths, or the unusual, like squill, crown imperial, giant onion or guinea-hen. A small investment of time and money this fall will reward you with beautiful flowers next spring.

Selecting Bulbs After deciding which types of flowers you want in the spring, select only firm, solid bulbs for planting. Avoid bulbs that are shriveled or lightweight. Bulbs that are discolored by mold or that contain soft spots also should be avoided. Size matters when selecting bulbs. The bigger the bulb, the better the flower display. Smaller bulbs often bloom but you get more with the larger bulbs.

Planting Bulbs October is a great time to plant spring-flowering bulbs. The soil temperatures in early fall are ideal for good root development. However, some bulbs like tulips may emerge in the fall if they are planted in September before the soil temperatures begin to cool. Procrastinators can plant spring-flowering bulbs as late as December if the ground remains unfrozen.

Select the planting site as carefully as you selected the bulbs. The soil should be fertile and well drained. Bulbs planted in wet sites will often be short-lived. Amending poor soils will go a long way in ensuring dependable blooms for the spring and every spring thereafter. The more suitable the site, the longer the bulbs will last in the garden.

Most bulbs prefer a sunny site as well. Bulbs often are successful beneath a high branched deciduous tree because they usually flower before the tree fully leafs out. After the bulbs have finished flowering, many can tolerate the light shade from trees.

Bulbs generally are planted along the foundations of homes, in beds or borders for unobstructed views of the blooms. Consider planting them with ornamental grasses and other perennials that will hide the foliage as it yellows. Plant bulbs in large groups for maximum visual impact. Bulbs planted alone or in rows are not nearly as effective as large sweeps or drifts of color. For a naturalized look, simply toss handfuls of bulbs in the garden and plant them where they land. The smaller bulbs should be planted in large groups (20 or more) or elevated in a berm or rock garden so they can be seen easily. Bulbs with different bloom times can be mixed together for a long-lasting display.

Proper bulb depth is another important planting requirement. The general rule is to plant the bulb at the depth of two and one-half to three times the height of the bulb. Tulips, daffodils and hyacinths often are planted six to eight inches deep. The smaller bulbs like squill, snowdrops and crocus often are planted three to four inches deep. Larger bulbs can be spaced four to six inches apart while a two to three inch spacing is more suitable for the smaller bulbs.

Don't forget to plant your bulbs right side up. This means planting the pointed end up for bulbs like tulips, daffodils, hyacinths, squill and many others. For some of the more unusual bulbs or bulb-like structures, it can be harder to tell which end goes up. If no roots or buds are apparent, you can plant some bulbs on their sides. The bulb will find the sun and bloom normally with only a little extra effort.

There are a number of tools made for planting bulbs. Bulb planters, trowels and auger attachments for electric drills are available to assist the gardener in bulb planting. For a mass plantings of bulbs in an area, remove the soil to the proper depth with a shovel. Place the bulbs in the desired arrangement or pattern and then carefully backfill with soil.

Fertilizers like 5-10-5, Bulb Booster or Bone Meal can be incorporated into the soil at the time of planting. Bone meal often is slower acting and more expensive than the others. These fertilizers are more important for the development of next year's bulb than they are for the upcoming flowers of this year's bulb.

After planting be sure to water the area thoroughly to provide plenty of moisture for root growth. Adding a light blanket of mulch on top of the soil will moderate soil temperatures. This will allow the bulbs a little more time for root growth before the ground freezes. The mulch layer also will conserve moisture in the soil the following summer.

Many garden centers and garden catalogs offer a wide variety of spring-blooming bulbs for sale. With a little planning and effort this fall you can be enjoying their cheery blossoms next spring.

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ml: isugarden


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