Dendrobium with no flowers!

[Tarryn]

Hi everyone,
We bought a dendrobium from an orchid seller that we met at an orchid show last year. It's quite a big plant with lots of branches and in a beautiful hanging basket. We've put it on a good spot and since we've had it, it's almost doubled in size! I've even had 3 keiki's off it, but NO flowers!!!!
Is there anything I can do to stimulate the flower growth? I have been feeding it once a week and it should be flowering now as this is their season, but there are no flower spikes at all! I read on one of the forums here that some Den's don't produce flowers, just keiki's. is this true?