I have a friend who grows blueberries in containers and has a different variety in each pot. She selects a potting soil with a low pH (acidic soil) and adds a bit of compost too. Then, she watches the amount of water they receive and is consistent with watering. However, the plants dislike wet feet so good drainage is important. She fertilizes once a month with a fertilizer that has aluminum sulfate. When the soil is the right pH level (4.5-5), the plant will flower and produce berries. A soil test can be helpful. Remember, that birds really like the fruit so you may want to net the plants so you get first dibs!
Thanks for writing,