Growing one’s own

Growing one’s own

I have a tiny balcony where I plan to grow some edibles this summer in the hope of cutting my food budget. I already have some tomato, strawberry and herb seedlings growing happily in my windowsill in preparation for later transferrals to the great outdoors, but after I set them free I will still have some space left on the balcony. So: what vegetables can I grow in (comparatively) little soil? I would particularly like something that's fairly prolific and bulky, and for preference not easy to fail with - I am not a natural gardener. Also, I live in Northern Europe, so the growing season is short, say from May to September. Any advice or tips on this sort of amateur crops growing is, as always, very much appreciated.
Lilac problem

Lilac problem

My Winter Park Apartment :)

My Winter Park Apartment :)

Hawaiian Schefflera

Hawaiian Schefflera

My Painted Forest

My Painted Forest

Pest Problem on Basil

Pest Problem on Basil

The bastards are back!

The bastards are back!