Tracey, I had never had luck with them either. So when JMorth offered me some last year, I said no thank you. Then this year, I asked him if he had any for sale, as I do love them, and I got a few from Jack. They were very large, compared to what I had ever received before, and all sprouted and are doing well. So, I think those little bitty ones you buy commercially might not have enough oomph in them to flower. I don't know for sure. But I've sure had excellent luck with the ones from Jack.
Picture of mine will be soon, they're covered with buds.