These articles are written to apply to the northeastern corner of Illinois. Problems and timing may not apply outside of this area.
October Time for Planting Spring Bulbs
October 8, 1998
Spring flowering bulbs typically provide the first colorful blooms after the snow of winter. Most species are dependable and can flower season after season. Some also make excellent choices for naturalization of the backyard. October is the time for planting.
Since bulbs are expected to keep returning for several years, it is important to prepare planting sites properly. Good soil drainage is probably the single most important consideration. Add compost, peat, rotted manure, or other organic matter to improve heavy clay soils. Work it into the upper 8 inches of soil.
Adequate soil fertility is also important. Use a complete commercial fertilizer, such as 5-10-5 or 5-10-10 at a rate of about 1 pound per 100 square feet of surface area. Work this thoroughly into the upper 4 to 6 inches of soil. Bulbs actually have formed their flower buds prior to planting, but fertilization will help increase production starting the second season.
Keep in mind foliage of most bulbs needs acceptable light in spring to help produce good flowers again the following season. For this reason, planting under large shade trees often causes problems. Species such as crocus, winter aconite, snowdrop, and Scilla sibirica usually do well under trees. Also allow foliage to turn yellow before removing in late spring.
There are many ways to use bulbs in the landscape. Mass plantings in solid beds, groups clustered in perennial beds or rock gardens, borders along walks or patios, and foundation plantings are all good choices. Annuals can be scheduled to follow spring bulbs.
Proper planning can provide color for most of the spring. Snowdrops (Galanthus) and winter aconites (Eranthis) start off the season in early March, followed by crocuses, scillas, and grape hyacinth (muscari). Then come hyacinths, narcissi, daffodils, and tulips; with cultivars providing variation in blooming time.
Plant bulbs this month so roots have time to get started. As a general rule, the depth of soil above the bulb should be about twice the diameter of the bulb. Allow adequate space for bulbs to grow, especially in naturalizing plantings. Planting details usually come with bulbs.
Garden centers have a good selection and thereีs plenty of time left for planting!