Potted plants for my 4th floor flat balcony?

Thing is I don't know what would be suitable, like what kind of flowers and if I can get a blueberry plant. Also does one need to change the soil of potted plants frequently? If so I buy an extra pot yes?
Apparently plants arrive with just the pot. Assuming I already know how to care for the plants, what do I need to buy and have before ordering plants? I know I'd need saucers for drainage, but what else?
Let me type the scenario for you if it will help.

I have a balcony, in the south of England where it can get windy, and I want to put something out there. I decided on a fruit plant, a couple herbs and flowers. What do I do to care for them during, say, a year?

I am sorry, I simply don't know much about this. But I do like nature, and I'd love to look at my balcony from the outside and see it as a pleasing view.

 

What direction does the balcony face?
Blueberry needs an acidic soil so you will need some ericacious compost for that. For herbs grow basil as an annual and parsley as a potential perennial (both can be bought from a supermarket and potted up a size or two). Sage (Salvia officionalis) will probably prove hardy.
Flowers? Why not try some climbers up a trellis or along the balcony railings?