The Azalea likes to be in a light place, but avoid direct sunlight. The Azalea also does not appreciate trip. The rhododendron prefers room temperature (15 to 22 °). If the Azalea is in a cooler place, you will have longer flowering pleasure.
Always keep the root ball of the Azalea moist but make sure that no layer of water remains in the pot. This causes root rot. If the root ball feels dry, you can place the pot in a bucket of water "for 15 minutes", so that the root ball can be filled with water. Do this once or twice a week depending on the temperature.
To prevent pests and keep your plant nice, it is important that you water the plant occasionally. This ensures that the dry air that is caused by the heating in the house cannot be a burden to the plant.
A healthy Azalea basically needs no food during flowering "which can last up to 6 weeks"!
The Rhododendron has few or no problems with leaf damage.
Repotting the azalea is not really necessary. If you still want to do this, take a pot that is at least 20% larger. Remove faded flowers from the azalea and leave the plant in a cool place until the next flowering.
The original origin of the azalea is Japan and China. As far as known surfaced in the Netherlands around 1680. The Azalea was brought by the VOC ships.
The Azalea has few problems with diseases. If there is too much leaf fall, this may indicate that the houseplant is too warm and / or too dry. Dipping the root ball will certainly help to prevent leaf fall.