My name is Martin Stone and my student, Shelton Slack, and I are working
on a research project growing _Zephyranthes grandiflora_. We are at
Western Kentucky University in Bowling Green, about an hour north of
Nashville, TN. We experience warm summers and cold winters and are
located in USDA hardiness zone 6 which means in an average winter we
will experience at least one low temperature between 0 deg F and
negative 10 deg. F. We have divided my large, old, potted clump into
smaller pots and are growing them in a greenhouse with temps no cooler
than 65 deg. F. We want to observe their flowering and try to answer
the old question about what induces flowering. They are growing well
after having been potted since September. We would like to know:

1. Is there a period after transplanting during which flowering does
not occur? How long do we wait?
2. Is flowering sensitive to the daylength?
3. and the big question: Does anyone have clues into the nature of the
flowering? There is not much scientific literature out there and the
two main sources are a little dated and conflict.

On a personal note, I have grown a potfull for the last dozen years from
a single corm. They are all clones of the original plant, which is a
bonus in this study. They stay outside until winter, when I bring them
into the greenhouse. But in the summer, I water my pot with the hose
every day and I see sporadic flowering. After a rain, there is a burst
of flowers a day or so afterwards. I believe the flower buds are
pre-formed and staying dormant until something about a rain event
triggers them to elongate and open. Is it temperature fluctuation
associated with a rain event? Is is cool rain water? Is it a drop in
barometric pressure (seems unlikely but who knows?). What do you think
and what are your observations?

Thanks in Advance and I look forward to your advice and thoughts.
My Best,
Martin

--
Martin Stone, Ph.D.
Assistant Professor,
Leichhardt Professor of Horticulture
Department of Agriculture
Western Kentucky University
1906 College Heights Blvd. #41066
Bowling Green, KY 42101-1066
Office (270) 745-5963
Fax (270) 745-5972