From http://www.unsv.com/voanews/specialenglish/
Ever since that time, the Netherlands has been the world's biggest producer of tulip bulbs. Tulip bulbs alone are a forty-one million dollar export business.
In the northern part of the world, most tulips by now have already been planted in the ground for spring flowering. But another way of planting tulips and some other bulb flowers is growing in popularity. It is called forcing bulbs. This method is a way to grow flowers in the middle of winter.
This is how it is done. Use planting containers about ten centimeters across but not very deep. You can plant as many as three tulip bulbs, spaced about one centimeter apart. Fill the containers with loose, fertile soil. Chose large bulbs that are hard and do not show any signs of disease, like gray mold.
Plant the bulbs so their pointed end is just above the level of the soil. Water the bulbs well. Then store them in a cool, dark place. Bulbs need temperatures of about five to ten degrees Celsius to begin to grow. Do not let the soil get dry, but do not put too much water either.
After six to ten weeks, the bulbs should have leaves about several centimeters long. The roots should be well developed. Move the containers out of the cold. Place them where they will receive moderate light.
Experts say the bulbs store enough food to produce flowers, so there is no need to fertilize them. About four weeks later, in the middle of winter, the bulbs should produce flowers.
This VOA Special English Agriculture Report was written by Mario Ritter. This is Steve Ember.