Seed pods - good or bad?

diana chapman
Tue, 29 Jun 2004 08:43:43 PDT
> > Daar Diana,  Have you found that Calochortus seed
> set affected blooming the following year?  Bob Werra

Well, I'm not sure!  It seems that Calochortus don't bloom every year.
Whether this is related to seed production or not I haven't tested out - but
this sounds like a good future project!  In the wild you can get spectacular
bloom in a good year and almost none the next year even if weather
conditions are favorable.  I've been fertilising my Calochortus regularly -
mostly to produce bigger bulbs - and they do seem to bloom more reliably
with fertilisation, but since there are lots of bulbs in each pot and not
all of them bloom it's hard to say whether it's because of seed production
or other factors.  Here I often cut off the flowers as they fade since I
don't want seed from plants that could possibly have crossed with other
nearby species, but I haven't noticed that removing the fading flowers and
preventing seed production produces more blooms the following year.

The Brodiaea group bloom much more reliably.  I wonder if this is because
they are corms and Calochortus are bulbs?

I have a theory that dry land bulbs of the western US often have internal
clocks that tell them not to bother to try to produce flowers and seed each
year.  The extreme example of this is Hesperocallis undulatum which can
remain dormant for several years, producing not a single leaf even though
other plants of the same species and in the same location have found
conditions suitable for growing. I grew these bulb for a while and thought I
was going a little crazy, since the first year I had dozens of shoots, the
next year about five re-emerged (OK, I thought the others had died), the
third year about eleven re-emerged, the next year three, until I tipped them
out - and they were all still there!!  This could be a survival mechanism
since weather conditions can often be unpredictable in the drier parts of
the west and if they all sprouted because of early rain, then there was no
more rain (this can happen) they would have wasted valuable reserves for
nothing.  With Hesperocallis, though, it would seem that each bulb has a
different clock telling it when to emerge.  Very interesting!


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