Latitude and its effect on bloom times

Thu, 28 Jul 2011 22:54:44 PDT
A. belladonna is a good species from which to form a test matrix. It is
grown in many places and there are no real differences between the clones we
all grow. 

In addition to soil moisture content another variable that might be included
is shade. I've noticed that clumps in shade bloom later, by and large.
Beyond that, it would become too complicated. For instance, some clumps have
formed large mounds and these tend to perform a little earlier than those
planted more recently and fully below soil (or gravel) level. But, let's
exclude that factor because it's going to get too complicated to compare

Year to year variation in time is also clear. Last year was later than this
but I have seen these same bulbs bloom weeks earlier than this also.

Lastly, there is one factor that beggars description. For reasons unknown to
me some clumps bloom every year without fail while others may miss a year or
two now and again. I know of one person whose bulbs never bloom at all. 

San Diego


Your mentioning of A. belladonna gave me an idea for an interesting case
study. If we could record the first blooming time of A. belladonna from
southern CA up to Washington of outdoor bulbs for several years in a row, we
could correlate it with various meteorological factors and hopefully come up
with some data on what causes these bulbs to break dormancy.

To start this, I have created a form that people can fill in. They can also
write in to the group or privately to me as well. Here is the form:…

Everyone, if you grow this species, please keep an eye out for when you
notice the buds break the ground and when the first flower opens. Thanks!


On Thu, Jul 28, 2011 at 8:52 PM, AW <> wrote:

>   Amayllis belladonna is going full bore right now.

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