I know it is way late in the season and I only started this on 11th of August but it seems to be very successful so far. Neither thing has been done before (in these ways) as far as I know.
So the pallet garden has an air gap (so no root rot from wet roots) and then water collection underneath. The water gets recycled back to the pallet garden for irrigation of the garden. There might be a vertical gardening component and it is watered by T-Joint airlift that is powered by a cheap aquarium bubble pump.
Playlist is at http://www.youtube.com/playlist?list=PL00C41C26C91A76BB&feature=view_all... The dripper irrigation is an offshoot of my dripper trackers for low tech solar. So I use a 3.7 liter glass jar of clean water to operate a waterclock that lowers a tube inside or outside a rainbarrel. I havn't found the ideal waterclock tap just yet but when that is figured out, I think that 5 or 6 days of constant dripper irrigation from a rainbarrel is realistic. http://www.youtube.com/playlist?list=PLkzXlmAwZTZdjGtjJpCYm2gSGVGwA033M&... I have been using both to water pallet gardens. The owner of an environmentally friendly furnature store in victoria is dillivering 20 free pallets to me probably next week to try it on a much bigger scale.
Anyway, I know it is a bit late for most of Canada. It is working so sweetly so far, just needs more people to try it.