Hot pepper plant
Why does my hot pepper plant remain very healthy, but peppers keep falling off?
Certified GKH Gardening Expert
There are many causes to this. Usually it is temperature. They need to have a difference between night and day temperatures to fruit properly, and the daytime temps need to remain in the 80's if not slightly higher. Hot peppers need a very long season to fruit, so anything you can do to help that along will help.
The next problems will be over, and underwatering. Usually overwatering. They can withstand some drought so underwatering is usually not the issue. It is best to let the soil dry out almost completely between watering.
The last cause is usually lack of light. If these are outdoors, make sure they get as much full sun as possible. The more the better. If they are indoors, you will need at least 200 watts of horticultural lighting to produce fruit.