PASCO, Wash. -- In past years during the fall, I've answered some of the frequently asked questions about the basics of growing spring flowering bulbs.
This week and next, I'll attempt to address some of the more advanced questions.
Q. What's the difference between a daffodil, narcissus and jonquil?
A. To the everyday gardener, there isn't really much difference between a daffodil, narcissus and jonquil, but daffodil experts like to split hairs. The botanically correct term for referring to the entire group of these flower bulbs is "narcissus," but gardeners often use the common term "daffodil" to refer to the entire group or just to the larger yellow flowered members of the genus. "Jonquil" is correctly used to refer to a smaller group of narcissus that have narrow, reed-like leaves and smaller fragrant flowers with flat petals.
Q. What's the ideal time in the fall to plant spring bulbs and when is it too late?
A. For our hardiness zone (USDA 6-7) the best time to plant bulbs is October through early November. If warm weather persists, wait to plant until the soil temperature goes down to 60 degrees. This is usually when the average night temperature drops to 50 degrees or cooler for about two weeks. You don't want to plant them in warm soil, but you should get them planted about six weeks before the ground freezes. This gives the roots of the bulb time to grow and become established before the soil freezes. Be sure to water the bulbs in to settle the soil immediately after planting and again through fall and early winter when conditions are mild and dry.
Q. If the soil isn't frozen, can I still plant bulbs in December?
A. It's not the ideal time, but if you find some bulbs that haven't been planted go ahead and plant them. The bulbs won't keep until the next fall, so you might as well give it a try. If the winter weather is mild, you might have success.
Q. What are pre-chilled bulbs?
A. Spring flowering bulbs need a period of chilling to break their dormancy and trigger flowering in the spring. Spring flowering bulbs planted in northern climates (USDA Zones 7 and lower) receive this chilling naturally when planted in the ground over the winter. Tulips and daffodils planted in warmer climates need to be pre-chilled before planting to bloom. Pre-chilled bulbs can be purchased through some bulb catalogs or gardeners can pre-chill their own bulbs in the refrigerator for 8-10 weeks before planting. In warmer climates, pre-chilled bulbs are treated as annual flowers.
Q. I've noticed a wide variety of prices when purchasing tulips and daffodils. Why is there such a variation in price?
A. One of the main reasons for different prices is the size or "caliber" of bulb which is a measurement of the bulb's circumference. When it comes to a particular variety of bulb, the more mature the bulb, the bigger the bulb, ... the more expensive the bulb. Bigger bulbs will have bigger flowers and put on a more dramatic display. The smaller, less expensive bulbs will still flower, but be less impressive. Bargain bulbs can add color to your garden without hurting your wallet as much. Keep in mind that daffodils have a greater tendency for repeat bloom and most hybrid tulips tend to flower only for a season or two at the most.
Next week, I'll answer a tough question about how to get tulips to re-bloom.
* Marianne C. Ophardt is a horticulturist for Washington State University Benton County Extension.