I can claim no great success with Calochortus, but, as no one else has answered, I suggest that standard procedures would be to plant the bulbs very deeply which helps promote bulb size and promote flowering. Flower buds should be initiated by heat soon after the bulb dies down for the Summer. Stem growth should then be stimulated by cold temperature fluctuations in Autumn and Winter. People do put pots of bulbs in the refridgerator to increase stem length if the flowers are prone to opening below ground, and to increase the size of the flowers Another factor may be that the bulbs would like to remain undisturbed for a few years before flowering. I know little about Calochortus, these are just some useful principles for cultivating winter growing bulbs. Peter (UK) On 22 May 2014 00:09, Giant Coreopsis <giantcoreopsis@gmail.com> wrote: > This may be an obscure one but here goes: > > Season after season these bulbs survive, but they aren't terribly robust > (just a single blade) and they don't ever bloom. It's been that way when > they are planted in the ground and when planted in pots. This year they > were in partial shade in a mix of sand, peat, perlite and some other > organics. Any idea how to improve performance? > > I am in LA and C. greenei's range in the far north of California into > Oregon > (http://calflora.org/cgi-bin/species_query.cgi/…). > It's been suggested that I might want to mimic a cold winter. How would I > do this - eg, is it as simply as putting the pot in my refrigerator for a > couple of months over the winter? > >