We need to know a bit more about the balcony - whereabouts in the world are you? Which way does the balcony face? Does it catch the wind? How high up is it? What sort of containers have you got or are you going to get new ones? What sort of flowers do you like - do you want colour or foliage - do you like large structural plants or pretty flowers in pots?
Lots of info needed please
b2p....I'd echo Dove. More info needed to help you plant up a beautiful balcony area
I think I'd try pelargoniums - including the trailing type (the sort of flower you see on pictures of traditional Swiss chalets). Pelargoniums are native to S. Africa, so I think they could stand the high light levels that you have.
Take a look here http://www.sarahraven.com/articles/pelargonium_groups.htm
Pots of scented flowers too would do well. If you like to use herbs, consider some of the mat forming or trailing types. Nasturtiums would give you plenty of colour .....trailing or upright. Check around and see what others with similar aspects are growing too....always a good idea when starting from scratch.
Have a good time choosing and planting