October 2000
Plant of the Month
Spring Flowering Bulbs
by Reprinted from the MNLA Northern Gardener Series

Plant of the Month
October, 2000

Bulbs are one of the quickest ways to add color to the landscape. Many fall planted bulbs are among the first flowers in spring and with some of the brightest of colors.

A bulb is technically a particular type of overwintering storage organ of a plant. But the word “bulb” is often used as a general term to include bulbs, corms, tubers and roots of plants. That is how the word “bulb” will be used in this article.

Bulbs are generally divided into two categories. The first category is hardy and can be left in the ground over winter. These are best planted in the fall although some, such as lilies and peonies, can also be spring planted. Tulips, daffodils, hyacinths and crocus are some of the more popular fall planted bulbs that will flower in the spring. The other category is the non-hardy types and these are planted in the spring, dug in the fall and stored for the winter. Examples of these non-hardy types would be tuberous begonias, gladiolus, dahlias and cannas.

Hardy, Fall Planted/Spring Flowering Bulbs

Fall bulbs require good drainage to grow and flourish. Poor drainage will lead to bulbs that become diseased and fail to come up. If drainage is poor, correct it by adding an organic amendment such as compost or peat moss to the existing soil, or raise or slope the bed to help eliminate excess water.

When to Plant
Spring flowering bulbs need to be planted in the fall. To encourage good root development planting in September and October is best. This early planting allows good root development and better flowering the first year. There is no need to be overly concerned if growth should begin to emerge on newly planted bulbs in the fall. This happens frequently and there is little if any correlation with winter injury.

How to Plant
Begin by preparing the planting area, especially in heavy or compacted soil, spade or rototill the area 6-8’ deep. Fertilizer, which is generally beneficial for long term performance, should be incorporated at this time into the rooting area of the bulbs. A good bulb fertilizer such as an 8-8-8 or similar analysis, should be used. Ask your garden center expert what planting depth is best for each particular bulb. Watering, especially when conditions are dry, is beneficial in settling the soil and encouraging rooting.

Space the bulbs according to their ultimate size. In general, large bulbs should be spaced from 3 to 10 inches apart and small bulbs from 1 to 2 inches.

Splitting and Replanting
As long as the flowering is satisfactory there is no need to disturb fall planted bulbs. However, if flowering begins to suffer you may want to consider digging your bulbs after the foliage has died which will normally be in July or August, and dividing or splitting them up. After digging, allow them to thoroughly dry before splitting and then replant in the fall as described previously.

Care in Spring
Be sure to allow the foliage of spring flowering bulbs to turn yellow before removing it from the garden. This will allow the leaves to return food to the bulbs for the following spring’s flower display. Many gardeners will plant annual flowers around bulb foliage to hide it as it yellows.

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