WillC said:You are not growing your Cestrum nocturnum outside, so NY weather is largely irrelevant unless you keep all your windows wide open throughout the winter!
This is a plant that requires maximum indoor direct sunlight to bloom. Yours shows large stem space between the sets of leaves and that is a symptom of less than ideal light. Otherwise, you seem to be taking good care of it.
Move it to your sunniest windowsill. You may want to prune back some of the already leggy stems to keep the plant fuller and more compact. Keep the soil moist and it may need water more frequently as the light improves and the roots expand. Keep it moderately potbound to encourage flowering. It will also have to mature before it is likely to bloom, so be patient.
Berniecharli said:.... It's not flowering. It was just 3 inches tall when I got it but over a foot tall now and it has huge beautiful leaves, but no flowers? Why do you think it hasn't bloomed? Is it the weather in NY? I mean it is summer and it's hot and it is growing, so I doubt that's it....