I have never been successful with these in the past and am having another go. The secret to these in the UK, is to keep them out of the wind, but in full sunlight.
I have created a wall on one side and can fix plastic over it when it is windy. After 4pm I move the peppers to the side of my house so they are back in full sunlight. I am already seeing fruits growing.
I have put some slow release fertiliser pellets on top of the soil. I water the peppers once a day and am also spraying the leaves with water.
I will let you know how I go on and give you a further update in a month. Red peppers are just the more ripened green ones.