Getting Rain Lilies to Bloom

J.E. Shields
Fri, 22 Nov 2013 15:49:32 PST
Someone commented -- and I can't seem to find the e-mail with that comment 
-- that they had difficulty getting some rainlilies to bloom.  When I had a 
much large collection of rainlilies -- maybe 30 years ago -- I seem to 
recall I had the same trouble.  Habranthus concolor sticks in my memory as 
only rarely blooming for me.

Charles Crane commented to me when we were preparing his surplus bulbs for 
the BX that the key to getting rainlilies to bloom was having lots of 
really healthy roots!  The root systems on his bulbs were huge, and he had 
lots of bloom still going on in November.  A  large and healthy root system 
will need a good amount of space for the roots to fill.  Charles showed me 
single bulbs growing individually in tubes -- the bulbs were very healthy, 
but he says they never, ever bloom while growing in the tubes.  I conclude 
there is just not enough volume for lots of vigorous roots to form in a 
tube or in a too-small pot.

I have also found that a brief dormant rest period is very helpful in 
getting bloom.  Charles drives his bulbs into a dry rest period each summer 
when the greenhouses get their hottest.  When he resumes watering, the 
blooms follow.

I usually dry my bulbs off in winter, and water heavily right through the 
heat of summer.  I seem to get a reasonable amount of bloom from my 
presently very limited collection.  I suspect that the rest period is 
crucial, as is the mass of roots to support the bulb and its flower.  The 
precise time of the rest may not be; but if you are not getting bloom, try 
varying the time of year when you give your rainlily bulbs a rest.  Some 
species may just need a little fine-tuning to their annual cycles to get 
reliable bloom.

What experience have others had with getting rainlilies to bloom?

Jim Shields

Jim Shields             USDA Zone 5
P.O. Box 92              WWW:
Westfield, Indiana 46074, USA
Lat. 40° 02.8' N, Long. 086° 06.6' W

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