There has been a lot of breeding work done on vegetables in recent years to create some compact varieties which are perfect for patio gardening or for people with only a small patch of earth. You can of course grow some conventional varieties in a different way to cope with smaller spaces.
CLOSE SPACED VEG
Many veg will just be small if you sow and grow at close spacings. It is actually a common problem if trying to grow crops to full size but you could use it to your advantage.