Bird of Paradise Plant
I have two indoor Bird of Paradise plants and another potted one that I keep outside in spring through early fall. In the wintertime I keep it in an unheated garage in front of a large window where it gets good sun. I moved this plant outside a few days ago (I live in Greensboro, NC). I was THRILLED to see two flowers forming! Unfortunately, my other two indoor plants have never formed a single flower and I've had them 5-6 years. When new leaves come out (like a tube), they never completely unfurl. They try but stay tight. I try to help by starting at the tip to force them to open but haven't been successful. I don't think they're potbound but just can't get them to do well. I have them in a two story foyer with lots of sun/natural light. I use an all-purpose fertilizer when watering them every 10 to 12 days. Don't understand how the younger plant is blooming but the older ones never have.
Increase the amount of sunlight that your plants are receiving.
Do not repot, they prefer to be root bound.
Here is an article to refresh you on the care requirements.