Have you all come across the water pots occasionally stocked by Lidl? They are cheap (about £4 – £6), plastic, round or square or trough shaped, and I have been collecting them for some years for back garden growing and use on my plots. The top two thirds or so is a space for compost and plants, and the bottom, underneath a removable floor with a wicking system, is a water reservoir. The great advantage, obviously, is that you do not have to water every day, and in cool weather it takes a week or more for them to dry out. They are a cheapo version of “earth boxes” which are very expensive (you can make your own, but I prefer the Lidl ones to my own untidy efforts). They are not things of beauty, but one could enclose a group of them inside some pleasant low fencing, I suppose. You have to buy the compost as garden soil apparently does not work, but it is re-usable if fertilised.
http://www.organiccatalogue.com/p2670/EARTHBOX-Green/product_info.html