I want flowers!

[Calliope]

Hi. I'm new to growing phalaenopsis orchids. I only have two (I did have 3, but we won't go there). One was flowering when I bought it and that's why I'm all potty about them. It flowered for months, MONTHS I say! There was something about the pure white, waxy petals that was extremely intoxicating. My new orchid comes from a nursery and it said it was ready to produce a flower spike within the next 6 months. I've cosseted my new babies, fed them once a week with special Phal food I bought from the nursery, kept them in a nice warm room and given them indirect sunlight. Nothing! Not even a new leaf. They are growing in good quality sphagnum moss and the leaves look healthy enough. It's winter here. Is that why they are not flowering? How can I get these creatures of fine sensibilities to do something?