Forcing is the process of making a bulb bloom out of season. Tulips normally bloom in April and May, but manipulation of the natural blossoming cycle can produce spring flowers in the middle of winter. Choose the largest size bulbs since they will produce the best quality blossoms. Clay, glass, plastic or any container will work for forcing tulips.
Mix equal parts of potting soil, sphagnum moss and perlite. Drill holes in the bottom of your container if it does not have good drainage. Fill the container 3/4 full with your soil mixture.
Place the tulip bulbs on top of the soil close enough that they almost touch. Lay the flat side of the tulip bulbs so they are facing the edge of the container. When the foliage grows, the large tulip leaves will grow over the plant pot rim.
Add more soil to the top of the plant pot, but leave the noses of the tulip bulbs poking out. Water the plant pot well.
Store the potted tulips in an area with temperatures between 40 and 45 degrees F. like a refrigerator, basement or shed for 15 to 17 weeks. Keep the bulbs in total darkness and water regularly.
Bring the tulip bulbs into an area with indirect light. Place the pot in a cool area with temperatures of 50 to 60 degrees F. until green growth is seen usually in four to five days.
Move the tulips to a warm location of 60 to 70 degrees F. with bright light. Keep the tulips well watered while growing. Blossoms appear three to four weeks after the plants are removed from cold storage.