Looks to be a bird of paradise - most likely the white, Strelitzia alba. They will grow 15 - 20ft in height
I think you're right, but I know it as Strelitzia nicolai. I'm not an expert, but I think this is the one with the white and navy blooms, some may say black, but the waxy bloom on the spathe makes it look blue to me. Whatever, interesting flower, tropical look and less common than Strelitzia reginae in my area. We grow both outdoors year round.
