Ornithogalum failure to flower
Nathan Lange (Mon, 08 Dec 2014 12:45:45 PST)

Since most commercially grown Ornithogalum dubium crops likely
consist of genetically identical individuals, I don't think comparing
their flowering to genetically heterogenous populations in situ is
valid in this instance. Significantly less than 100% flowering for a
commercial O. dubium crop suggests three possibilities.

First, the bulbs may not have yet reached a state of physiological
maturity following the last vegetative growing cycle even though the
foliage has already died down (I'm not referring to bulb size here,
although the bulbs do have to be large enough to flower). For
example, as is frequently the case, the foliage prematurely died
because the plants were not adequately cared for after the flowers
senesced, or perhaps the bulbs were harvested too soon from the soil
resulting in the bulbs not fully maturing. The temperature during the
bulb enlargement stage of many species can also affect the
physiological state of the bulbs at harvest.

Second, the bulbs reached a state of maturity and became fully
dormant but there might now be a dormancy breaking requirement (not
necessarily warm temperatures) needed before the bulbs can perceive
the floral induction stimulus (presumed to be warm temperatures).
Assuming such a dormancy breaking requirement even exists for this
species, without meeting this necessary dormancy breaking
requirement, subsequent warm temperatures will not induce flowering.
Such a dormancy breaking treatment could be something as simple as a
period of relatively cooler (not vernalization) or even warmer
temperatures prior to the warm floral induction period.

Finally, the third possible reason for less than 100% flowering is
that the warm floral induction stimulus was inadequate. The bulbs
were mature and dormancy (as defined by the ability to respond to a
floral stimulus) was broken but subsequent temperatures were not warm
enough and/or for long enough. In the situation of growing plants in
pots, not fulfilling all three of these potential requirements could
easily account for less than 100% flowering.

That being said, Hugh's comments are spot on. Whatever their needs
for full flowering, the major wholesale growers already have this
species figured out.

Nathan

At 10:15 PM 12/7/2014, you wrote: