Ornithogalum failure to break dormancy
Nathan Lange (Sun, 07 Dec 2014 17:54:39 PST)

One possible solution is to store Ornithogalum
dubium bulbs completely dry and unpotted in a
paper bag on top of a refrigerator, but I would
only do this after checking the temperature there
first to see if its warm enough (above 22C, 72F)
and not too warm (maybe above 30C, 86F, which I
realize is much cooler than your typical day time
summer day in inland California, but I'm talking
about constant 24 hour day/night temperature).
Heating mats would be another option.

As I previously posted,
http://www.jhortscib.org/Vol79/79_4/12.htm , this
study suggests that the optimal Ornithogalum
dubium bulb storage temperature for flowering is
between 22C (72F) and 30C (86F) but it's hard to
say without seeing the complete article and this
study was very limited to only one, arguably
short, storage duration of six weeks. Even at
these temperatures, the percentage of bulbs that
flowered was below 100%. Longer warm storage
durations would likely increase bulb flowering
percentages. At higher temperatures, 35C (95F),
the number of florets per bulb decreased, so
while the percentage of bulbs that flower may
increase with increasing storage temperature over
a given temperature range, the number of florets
per inflorescence decreases. Similar results are
often seen with other unrelated species requiring
vernalization: over vernalization ensures 100%
flowering but also results in fewer flowers per
plant. The key is always to find that optimal
temperature treatment that maximizes both flower
number and flowering percentage.

An earlier study,
http://www.actahort.org/books/430/430_34.htm ,
generally agreed with the one above and
recommends storing harvested bulbs at 25C (77F)
in addition to keeping them at 17C (63F) for four
weeks prior to planting for potted plant
production, although it's unclear from the
abstract how these particular temperatures were selected.

Another source (Netherlands bulb industry?)
recommends a "dormancy-breaking requirement" of seven weeks at 28°C (82F):
http://prod.bulbsonline.org/ibc/binaries/…

Nathan