These days, plants are likely to appear in Japanese culture in a somewhat different light -- as the inhabitants of guerilla flowerpots in the urban jungle, or as chic lifestyle accessories in "avant gardening" magazine Planted (currently celebrating its sixth issue with an exhibition in Harajuku).
For a globalized consumer society which can import most of its food from poorer neighbours, tight space, hilly landforms and the difficulties of irrigation no longer pose the problems they once did to Japan. However post-agrarian a society gets, though, water is still a precious resource, and some say a world water crisis is one of the less pleasant things we're likely to be facing this century, as the world's supply of fresh water runs out (just, ironically, as sea-levels begin to rise).
Virtual Water is a double-sided poster by German graphic designer Timm Kekeritz intended to raise awareness of the world's water crisis. On one side he breaks down the Virtual Water Inside Products (virtual water includes all the water used in the production of the commodity), on the other he shows the Water Footprints of Nations in terms of water use per capita per year.
The data on Kekeritz's map comes from this study by Hoekstra and Chapagain. It makes for interesting reading; the virtual water content of a 250ml glass of beer is 75 litres. A cotton t-shirt, if you count all the water taken to raise the cotton it's made of, uses 2000 virtual litres of water, and a pair of leather shoes uses 8000. In terms of national per capita water footprints, it's of course the US which wastes most water -- almost 2500 cubic metres per person per year (one cubic metre contains 1000 litres). China, India and Japan are the most water-efficient countries -- Japan's 1153.6 m3 puts it amongst the developing countries in thrift. Japan is certainly the only advanced country I've seen that runs a little tap off the toilet flush so you can wash your hands without using the sink -- and saving water is the logic behind the Washlet's recording of a flush (bashful ladies were said to flush unnecessarily to cover embarrassing noises, thereby wasting water, so I guess the electronic flushing sound is another kind of "virtual water").
To show that a sense of water's preciousness still runs deep in today's Japanese, here's my friend Tomoko Miyata live at La Générale in Paris, using carefully measured and tuned water in rice bowls as a musical instrument: