Forcing Spring Bulbs
Creating a beautiful indoor presence with spring bulbs is easy when you know how to force them to bloom. The most common bulbs to force are daffodils, tulips, hyacinths, crocus, paperwhites, and amaryllis.
To force bulbs you can plant them in soil or put them in a paper bag. Some bulbs can actually be forced in water, stone, or gravel. With the exception of amaryllis or paperwhites, the average temperature for forcing bulbs is 45 degrees F.
Forcing bulbs in water
Crocus, hyacinths, and narcissus (both daffodils and paperwhites) can be forced in water. Use clear glass, vase, or flat pottery and make certain that the water only touches the bottom of the bulb. Keep the container with the bulbs in a cool, dark room with temperature around 50 degree F until the root system is developed. This usually takes 6 to 8 weeks. Once the root system is developed, you can place it in a sunny location and watch it flower.
Forcing bulbs in pots using soil
If you decide to plant the bulbs in pots with soil, place them in a pot with drainage holes and use a mixture of potting soil with peat moss and a bit of sand for drainage. Plant them closely together with tips up and showing. Water the plants before you put them either in the refrigerator or outside to chill. Also, keep the pots moist during the chilling process. Since bulbs in the refrigerator dry faster, you may want to put plastic wrap, with holes, over the bulbs to help with moisture control. Paperwhites do not need to go through the chilling process. Amaryllis only need to go through the chilling process after you’ve been growing the bulb for a few years. Once the roots are established put the plants in a cool, low-light location for a week. This gives them a chance to adapt. After the week, you can move them to a sunny location and watch them flower.
Plant the bulb in a pot one (1) inch wider than the diameter of the bulb in loose, well-drained soil or on stones. If planted in soil, leave the top 1 to 2 inches of the bulb above the soil. Water well and keep it in a warm location. After the bud appears, keep the plant in full sun. It is important that the soil is kept evenly moist. If you want to force the bulb the following year, cut off the flowers after blooming to prevent seed formation and keep growing the foliage. Continue watering and fertilizing with a 10-10-10 fertilizer until the foliage turns yellow. Stop watering and cut back the yellow leaves. Place the bulb in a cool, dry place and allow it to rest.
Bulb Forcing Requirements
- Amaryllis needs eight weeks of chilling time in 55 degree F temperature. The only bulbs that need this chilling time are ones you’ve been growing for a few years.
- Paperwhites (Narcissus) do not need any chilling time period.
- Crocus needs six weeks of chilling in 45 degree F temperature.
- Daffodils (Narcissus), but not Paperwhites, need eight to ten weeks of chilling in 45 degrees F temperature.
- Grape hyacinth need six weeks of chilling in 45 degrees F temperature.
- Tulips need 12 weeks of chilling in 45 degrees F temperature.