Flower crops are season specific and blooming period under traditional culture is short, varying
from few weeks tot month, depending on the geographical location. This is one of the major
limitations in floriculture subsector. The growers are forcing flower crops to produce flower
during off season or predetermined time through manipulation of growing conditions to fetch
good returns and increase the duration of availability in market. In some bulbous species such as
tulip, narcissus, hyacinth, lilium etc. thermos periodic changes are required to induce flowering.
The specificity of temperature requirement for different stages of flower initiation is manipulated
for controlling the flowering. There are 3- phase forcing system for ornamental bulbs i.e.
production, programming and greenhouse phase. There are two main techniques for
programming underlying bulb forcing i.e. Rooting room Forcing and Non-rooting Room Forcing
schedule. Hence, programmed blooming results in year-round availability of flowers for
floriculture industry.