I purchased white Z. candida in 2014 and only saw 3 blooms (out of 10 bulbs) that summer. I grow them in pots and overwinter dry in the pots like jmorth. Last summer they produced many blooms throughout the summer. I'm guessing getting crowded in the pots helped. Last summer I was not good about keeping the potted plants fed like I do most years, not sure if they prefer very light feeding or if that was a fluke?