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Forcing Bulbs


Fall in Calgary can be pretty drab. Many people will spruce up their indoor scapes with forced bulbs. The idea: you “trick” the bulb into going through winter at some other time of the year, then trigger the bulb to “wake up” and bloom.Tulips

Most bulbs will need a rooting period of 12-15 weeks @ 5-9ºC. You can store bare bulbs in the fridge in a mesh or paper bag until you are ready to plant. But to produce flowers, the bulb will need to root in soil for the entire rooting period. A cool basement or fridge are good places.

Choose the bulbs you want to force and plant them at the appropriate depth (usually twice the width of the bulb) printed on the package. Then store in the fridge for the number of weeks needed (see table below). Remove from the fridge. At this point the bulbs should begin to “wake up” and will grow and bloom.


  • Plant bulbs closely together but not touching.
  • Plant tulips with the flat side facing the edge of the pot
  • Shorter cooling periods will result in shorter stems. Cool for longer periods for taller stems.


Bulb                                           Weeks of Cold      Weeks to bloom
Amaryllis None 6 – 8
Crocus 15 2 – 3
Daffodil 12 – 14 3 – 4
Hyacinth (not chilled) 11 – 14 3 – 4
Hyacinth (chilled) 8 – 11 3 – 4
Narcissus 15 – 17 2 – 3
Paperwhites None 3 – 5
Tulip 14 – 20 3 – 4