We live in southern Arizona and have a patch of land 4' by 20' that runs along a block fence. It is shaded most of the day by houses on either side. With only a couple hours of actual sun rays hitting the area, will anything grow? I would like to try some basic everyday things (lettuce, cucumber, tomatoes, root veggies). Do the dimensions of the garden matter? Are we able to use the drip line that we just put in?