Fritillaria Raddeana Question

Peter Taggart
Sun, 16 Sep 2012 00:42:02 PDT
Plants seem to know when Autumn has arrived regardless of whether it is at
the end of July in Glasgow, August in Dusseldorf , or October in Maryland
When temperature oscillation and moisture trigger growth  -the bulbs start
to root. To store the bulbs below about 48 Fahrenheit, (9 degrees C), in a
dormant state will put the internal development of the bulb into winter
mode, without the associated seasonal ability for rooting and vegetative
development. To then remove the non rooted bulb, in its overdeveloped
internal state, to a warm environment in late Summer to experience a second
chilling as Autumn approaches would seem a very strange procedure.

I am suggesting that a domestic refrigerator  -39 degrees Fahrenheit (4
degrees C), is too cold for the summer storage of winter growing bulbs (if
they are to grow naturally and in character).
Such temperatures might be useful to prolong the winter growing season in
areas where low temperatures might not last long enough for winter growing
bulbs to complete their growth cycle.

The point of  my links on climate was to compare Summer temperatures in
Maryland USA  to Fritillaria raddeanas native summer temperatures in Iran.
Peter (UK)

On Sun, Sep 16, 2012 at 1:52 AM, Jim McKenney <>wrote:

> A good place to start, Peter, might be to define chilling.
> Late August soil temperatures in Düsseldorf are probably chilly compared
> to Maryland soils at the same time. When I suggested that bulbs be
> refrigerated in late summer, it was with our local conditions here in
> Maryland in mind.
> But I agree with what you are saying about the need of some taxa  for
> warmth during dormancy - in fact, I've often wondered if this might explain
> why the Californian Fritillaria are so difficult in the UK, where so many
> other species appear to be very easily managed and flowered.

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