A lot of vegetable gardening authorities, whatever that means, suggest planting vegetables on raised beds but in South Australia and a lot of other Mediterranean zones, this, to me is madness. In places where summer water is oh so precious, we do not need to provide drainage, we need to be preserving every drop of water for the plants. If you look at raised garden beds, you often find the paths, which are lower than the beds, grow lush crops of weeds and grasses!
Jude Fanton has found these beautiful gardens in the arid zone of western Rajasthan, India, which show what can be achieved when we look at our own environments and not those of people on gardening shows in other climates, even in the same country as ourselves.
I don't know if you remember my terracotta pots idea, but it comes from looking at my own situation and works wonderfully well in doing several things to help plants get through our extreme summer heat.
First, unsealed, unglazed terracotta is simply fired clay and is porous so the water moves very slowly out through the pot into the soil, keeping plants such as lettuce and bush beans turgid and fresh even in the full sun on days over 40C.
Secondly and probably equally as important, the water in the clay pot, covered with a tile, keeps the surrounding soil temperature from rising too high. It is high soil temperatures which damages the roots of plants and causes them to burn off, in extreme heat, and stop the roots sucking up water even if it is available.
For more on this experiment see these updates:Using tank water without a pump
Recently I experimented with another similar idea, where I put an open, plastic bowl full of water in the middle of a large, shallow tyre-pot and surrounded it with tiny, caterpillar-eaten bok choy seedlings. I could not believe the speed of their growth compared to seedlings I planted elsewhere and they were ready to eat in 21 days! I am not sure why it worked, maybe the water heated during the day and kept the soil temperature warmer over night..... maybe it was the humidity provided by the water..... maybe both.