When your gardening space is relegated to a small strip of ground and a couple of containers, companion planting is your best friend---your forced best friend, but a best friend none the less.
Case in point:
Here you have my late summer planting of tomatoes. I planted my two favorite varieties, Brown Berry Cherry and Cherokee Purple. Because we can grow tomatoes well into October here in Los Angeles, I decided to plant a late Summer crop. I realized this Summer that the spot where I'm currently growing my tomatoes isn't necessarily the best spot---it only gets about 5 hours of sun. The tomatoes are doing fine, but I wondered if planting them just across the entrance to our apartment would serve them better since it gets sun practically all day. Only problem was the box I wanted to use was slated for beets, so companion planting it is!
I have no idea whether these two veggies like to grow next to each other, but so far they seem to be playing fine. I figure that beets like it on the cooler side so once the tomatoes grow taller they can act like a natural umbrella to partially shade the beets. I guess I'll have to wait and see.