Experts and BHG readers answer.
Sweeten up strawberries
You can't change the nature of the plant itself. I can't guess why they are bitter or small. It could be that the patch has grown very crowded or old. After two or three years it's often best to start with new plants since strawberries get a variety of illnesses after they've been growing for a few years. You don't say how old your berries are, but I'd think about planting a new crop.