By Night Blooming Cereus I'm guessing you mean Epiphyllum Oxypetalum from your flat leave description. If overwintering indoors it needs a cool rest period. As low as 50 degrees if possible and less water. The light should be bright but not direct sun. Lack of light will keep it from blooming. Do you put it out during spring or summer? If so, wait until night temperatures stay above 50 and put it in as bright of light as possible but no direct sun. The flower buds are small and pointy at first and look different from new leaves. Mine doesn't bloom until summer however, so if you have buds they are early. If you leave it in the house consider artificial lights, I've bloomed them indoors before like that.

Thanks for the great info nightbloomer. Next year I will try overwintering it in the cool greenhouse instead of the house as it is probably too warm in here. I do protect it from freezing pretty religiously and keep it in the shade when it is out in the summer. Do you think I would have to protect it out in the greenhouse with some shade cloth or something. Our WI winter sun is pretty week, but it would be direct light out there.
Catrina

To be on the safe side, I would give it some shade in there. Watch the temperatures in winter, the species Epiphyllums are more tropical. I would keep it above 40 F. Also try to give it dappled shade in summer as opposed to deep shade. Too little light will keep it from blooming.

I also know that these plants like to be pot-bound and that might have something to do with their ability to put out flowers that will make it to maturity.

Thanks again gals,
Anne, I'm so glad to hear that they like to be pot bound. Mine is in about a 1 1/2 gal pot and I was thinking it needed to be moved to a bigger one, but wasn't looking forward to doing it as I think I would need help this time the plant is so big and I wouldn't want to break it. I wouldn't doubt if this was part of the problem as I have been going to bigger and bigger pots all along.
Catrina