If they are dark green, that means they are getting too much sun exposure. Move the plant to a less sunny area. If the leaves are yellow or even a brown color, this means that there is not enough sun exposure. Try moving it to a sunnier spot, such as a window ledge. If the leaves are a light green, that means there is a perfect amount of sunlight reaching it. The incorrect amount of sunlight can inhibit the blooming.
If the air seems too dry, try placing the plant on a tray and fill the tray with water so that the air fills with humidity as the water evaporates. Top off the tray as often as needed, to ensure the tray has standing water in it at all times.
