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Yates Association

Planting Bulbs for Spring Flowers
By, Sheri Mochamer

September 26, 2001

The nights are getting chillier, leaves are starting to fall, children are back at school, and many of us are preparing our gardens for winter. We are harvesting the last of the crops, getting rid of the remaining plant matter and doing what needs to be done to get ready for winter. However, now is also the time to be thinking of spring flowers and planting bulbs.

"Bulb" is a loosely used term to describe any plant that has a thickened or swollen basal portion. Many of the "bulbs" we plant for beautiful gardens are really "bulb-like" but not true bulbs. True bulbs are short underground stems surrounded by fleshy leaves. These leaves protect and store food for the baby plant (embryo) that is hidden deep in the bulb. Examples of true bulbs are tulips, daffodils, grape hyacinths, snowdrops, and allium to name just a few. Crocus, gladiolus and freesia are examples of corms.

Corms differ from bulbs in that these modified stems are not surrounded by fleshy leaves but rather by solid tissue. Other modified stems that are planted and have been called bulbs are irises and callas. These are really rhizomes which are creeping underground stems. Tubers, another underground stem type, include potatoes, tuberous begonias and ranunculus. Thinking of how potatoes grow is an easy way to remember some characteristics of tubers. They do not have leafy protection around the stored food, and have growth buds, called eyes. The last example of a modified stem that has been placed in the bulb group but is not a true bulb is the tuberous rhizome, or tuberous rootstock. Canna is an example of a tuberous rhizome, and these have characteristics of both the tuber and rhizome groups.

New York State has a perfect climate for spring flowering bulbs because they need to have a period of winter chilling in order for them to complete their life cycle. The time to plant them is in the fall when they use moisture to help establish roots. The bulbs go through a growing period but do not send up top growth because of ever decreasing temperatures. Winter chills keep the bulb in a period of rest. Springtime warmth and rain cause the bulb to begin sending up its top growth of leaves and flowers. After they bloom, the leaves make food then wither and turn yellow. That is the time to cut the leaves back, and that is all that needs to be done. The cycle will continue year after year with little assistance. Spring bulbs are one of the easiest kinds of flowers to maintain.

If you are planning to have your spring garden full of plants like crocus, tulips, daffodils, hyacinths, and more, hopefully you have already begun to plan what this garden will look like. You should put in an order for bulbs so that you can plant them this fall. If not, you still have time to purchase bulbs at local garden stores. You will need to know what to look for when buying bulbs, and where, when and how to plant them.

When you are buying bulbs, look for those that are firm to the touch and without blemishes or scars. Slight traces of blue mold should not be harmful to the bulb, but mold throughout can indicate the bulb has been stored incorrectly for a long time. Bulbs should also have little or no root or shoot growth, except for a pale growth bud at the top. The advanced growth would indicate that storage temperatures were too warm.
When you get the bulbs home, it is wise to plant them quickly so they can adapt to their new home. If you cannot plant them within a couple of days, store them in a cool, dark, relatively dry place. Keep them in the paper or mesh bags in which they were purchased. It is acceptable to store spring bulbs in the refrigerator, since they will be going through a chilled period.

When you are ready to plant, be sure your soil is prepared. Bulbs need to be in areas that have good drainage. That requires soil to be loamy or sandy. A word of caution about sandy soils: If there is too much drainage, the soil will be too dry. Loamy soil is best. Add organic matter to your soil if you are not sure. Organic matter not only helps with soil nutrition but helps with water retention and drainage.

Some people will put bulbs in flower beds, and some like to "naturalize" a lawn or meadow with flowers. Planting in a bed is easy. Dig the hole to the proper depth, put in the bulb with the root side down, and cover with soil. The proper depth will vary with size of the bulbs, but a general rule of thumb is to plant bulbs 3-4 times their height. For example, when planting a tulip bulb that measures 1 ½ inches, dig the hole 4 ½-6 inches deep. After the bulbs are covered, they should be watered thoroughly.

To naturalize a lawn or meadow, the method is the same, although you would be working around an existing lawn. You also would want to plant the bulbs randomly for the natural look. For smaller bulbs, use a narrow trowel, dandelion digger or garden knife to make a hole and wiggle it until the proper depth is reached. For larger bulbs, you may have to remove or fold back some of the sod, and dig to the proper depth. Cover the bulb with soil and the sod. According to Rodale's Successful Organic Gardening
"Annuals and Bulbs," the best bulbs for naturalizing are Lily leek, Grecian windflower, crocus, snowdrops, Spanish bluebells, grape hyacinth and daffodils.

As stated earlier, bulbs are one of the easiest ways to enjoy beautiful flowers. The care is minimal, with watering, fertilizing, and occasionally dividing the bulbs. Dividing spring bulbs should be done after the leaves have died back, which is in late spring. Lift the clump of leaves and plant matter with a spade or digging fork, and separate the "bulblets" by gently pulling them away from the mother bulb. These small bulbs should be planted in a "nursery bed" where, with water and fertilizer, they can grow to reach flowering size. This usually takes a year or two. Then the bulbs can be replanted into a regular bed.

In addition to planting the bulbs outdoors for springtime enjoyment, bulbs can be planted so that they will bloom indoors! Having beautiful flowers indoors can surely brighten up a dreary winter day. According to Rodale, most spring bulbs can be forced, which is the term used for encouraging bulbs to grow and bloom indoors earlier than they normally would.
While a variety of potting media can be used, regular good draining potting soil is just fine. Place the bulbs "shoulder to shoulder" in clay or plastic pots, in the potting soil so that the "nose" of the bulb is just peeking out of the soil. Water thoroughly, and place the pot in a cool spot for the "winter chill." This cooling place needs to be between 33-45 degrees. Some folks use an unheated garage or basement, while others use their refrigerators. If you have room in the fridge, be sure to cover your pot with a plastic bag (that has some holes in it) so the bulbs do not dry out. Check on the bulbs regularly (every week or so) and water if necessary. Look for signs of growth. Tiny white roots will appear in the drainage holes of the pot, and new shoots will appear at the top. For crocus, this can be as early as 8 weeks, for tulips and daffodils, this can take up to 12 weeks. When the shoots are 1-2 inches, place the pots in a cool, bright window. Water regularly, and enjoy the beauty!

There are many resources available about planting bulbs not only for spring, but also for summer and fall. These resources, along with other information, are available from Master Gardeners at Cornell Cooperative Extension. If you have any questions about gardening, please call the Master Gardeners on at 315-536-5123. Leave your name and question along with your return phone number and a time we can call you back with an answer. We look forward to your calls.


Cornell Cooperative Extension Yates Association
Last updated: 9/18/01

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