Failure to flower, was Amaryllis belladonna

Jane McGary
Tue, 11 Aug 2009 11:30:46 PDT
David Ehrlich wrote
>I am quite certain that the reason they failed to bloom last year 
>was simply that they hadn't had time to rebuild their reserves due 
>to the absence of foliage the year before. This is the same effect 
>that winter leaf-freeze would have.

Drought can also prevent geophytes from flowering the next year, or 
even from emerging at all if they're really drought-adapted.

I wonder if my rabbit- and deer-chewed fritillarias will fail to 
flower next year, having lost their scapes but mostly retained their 
leaves through at least the first part of their growth cycle. If they 
do fail to bloom, that could actually be an adaptive trait: if 
predators don't find their favored food two years in a row in the 
same place, they may not harm the plants often enough to kill them. 
(This winter, however, I'm screening off the bulb frames, preferring 
to rely on technology rather than nature in this case.)

I have never flowered Amaryllis belladonna here in the Cascade 
foothills, though I've seen it flowering up against the warm sides of 
houses in nearby Portland, 1500 feet lower down. The same goes for 
Nerine. During our recent heat wave, nighttime temperatures at my 
home were about 15 degrees F lower than in the city (e.g., 22 C vs. 
31 C at 11 pm). This undoubtedly affects flowering.

The days have cooled, with record lows for one date last week, and a 
few fall bulbs have presented their flowers: Acis autumnalis, 
Cyclamen hederifolium and the first little Colchicum species.

Jane McGary
Northwestern Oregon, USA

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