Extension News

October Is Time to Plant Spring Flowering Bulbs

Spring Bulbs

Note to media editors: This is the Garden Column for use during the week beginning Oct. 9.

10/5/2009

By Richard Jauron
Extension Horticulturalist
Iowa State University

Tulips, daffodils, crocuses, and other spring-flowering bulbs are a welcome sight in spring. To enjoy the colorful spring display, gardeners must purchase and plant spring-flowering bulbs in fall.

When purchasing spring-flowering bulbs at garden centers, select large, firm bulbs. Avoid small, soft or blemished bulbs. Store purchased bulbs in a cool, dry, well-ventilated location, such as a garage, until they are planted.

October is the ideal time to plant spring-flowering bulbs in Iowa. When planted in October, spring-flowering bulbs have sufficient time to develop a good root system before the ground freezes in winter. If weather permits, bulbs can be planted as late as mid to late November. However, late-planted bulbs will emerge and bloom later than normal the following spring.

Tulips, daffodils and most other spring-flowering bulbs perform best in areas that receive six or more hours of direct sun each day. All high quality bulbs should bloom well the first spring. However, tulips, daffodils and other bulbs planted in partial shade may not bloom well in succeeding years because of insufficient sunlight.

A few bulbs, such as snowdrops and Siberian squill, can be successfully grown in partial shade. Bulbs also need fertile, well-drained soils. Bulbs may rot in wet, poorly drained sites. Planting bulbs in raised beds may be the best option in poorly drained sites.

Plant spring-flowering bulbs in clusters or groups to achieve the greatest visual impact in the garden. When planting daffodils and tulips, plant 10 or more bulbs of the same variety in an area. Smaller growing plants, such as grape hyacinths and crocuses, should be planted in clusters of 25 or more bulbs. Plant bulbs at a depth equal to three to four times their maximum bulb diameter. Accordingly, tulips and daffodils should be planted six to eight inches deep, crocuses and grape hyacinths only three to four inches deep. Large bulbs, such as tulips and daffodils, should be spaced four to six inches apart. A three-inch spacing is adequate for crocuses, grape hyacinths and other small bulbs.

After planting, water the bulbs periodically (if the weather in fall is dry) to promote good root development.

Sometimes, winter seems like it will never end. However, winter eventually relents and is replaced by the sights and sounds of spring. Some of the most beautiful sights of spring are the colorful flowers of tulips, daffodils and other spring-flowering bulbs. Be sure to purchase and plant some spring-flowering bulbs in the landscape this fall.

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Contacts :

Richard Jauron, Horticulture, (515) 294-1871, rjauron@iastate.edu

Del Marks, Extension Communications and External Relations, (515) 294-9807, delmarks@iastate.edu