Christmas Cactus Blooming

Eric Nitardy ericn at
Thu Nov 30 18:36:54 EST 1995

lee.hunt at (lee hunt) wrote:

>In article <49b5fh$53h at>, Barry Mercer <bmercer at> says:
>>I enjoy Cacti... don't know much about them, but I enjoy them. (my 
>>spouce doesn't)  How do I encourage these things to bloom and just how 
>>dry should I let them be before I water.  The Christmas cactus I water 
>>once a week the "real" cacti far less frequesntly.
>>I recently read that keeping them very dark and very cool at night will 
>It is probably too late for flowers for this CHristmas if your palnts do
>not already have buds. Here in the Uk I keep the plants in a shady spot
>outdoors in the summer and bring them inside in the autumn. The plants will
>only produce buds if they have an uninterrupted dark period overnight ie about 
>12hrs. This should occur naturally as long as their is no artificial light
>Many Christmas cacti seem to have their main flowering period in November
>here. They should be kept dry whilst buds are forming, then kept moist after
>they appear
>Lee Hunt
Lee Hunt's comments on what sets flower buds on Christmas Cactus is
accurate but does not tell the whole story.  As noted,  one way to set
bud is to expose the plant to a series of uninterupted 12 hour +
nights, that is, leave them outside or in a room that is not
artifically lit during the month of October.  

Alternatively, exposing the plant to near freezing ( 0-5 degrees
Celsius) for 1-2 weeks will set flower buds.  Where I live, in
Minnesota, this method quite well--I let the plant go through one or
two frosts and then bring it indoors, usually Early October plus or
minus a week.  It has not failed in ten years.  Incidently, these
plants are surprisingly tough; They usually endure -3 degree Celsius
tempuratures before I bring them in with no damage to the plant or the

Eric Nitardy
ericn at  

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