Jean,
I really haven't noticed a big difference between well water and rain water. Mine seem to start blooming sporadically in early June or so. But they really take off starting in late July/early August. I water them really deep when we are not getting rain. I haven't fertilized mine at all. Here's a pic from a couple weeks ago, you can see they are planted next to Xanthosoma monstruosum ( Mickey Mouse Taro) and it likes a moist rich soil also.
Mine have come back reliably each spring.
