The second garden up the bank is the one I call the Middle Garden. It gets a bit more sun than the Bottom Garden. I've successfully grown all sorts of vegies in this garden so far including broad beans, brocolli, beetroot, lettuce, kale, spring onions, tomatoes, silver beet, peas, basil, parsley, cauliflower, rhubarb, globe artichoke... I'm sure I've missed a few.
The tomatoes did particularly well last year and I'm sure the keystone retainers have something to do with that. Being charcoal gray in colour they absorb a lot of heat during the day and are still warm at night especially at the height of summer, which the tomatoes seemed to love.