Sacha writes

All will need *some* watering if it can be arranged with a neighbour in
their absence but on the whole, they cope pretty well with dry
conditions - total drought would push anything to its extreme! And -
all joking aside - would your beloved cacti work there, Kay?

They'd work in the summer, but would only survive the winter if kept
completely dry.

I've never grown them so have no idea. Most of our Geraniums survive
on the rainfall the heavens provide with the occasional extra dollop.

The heavens are quite generous in your part of the world ;-)

If Kate can find a few cheaply enough to experiment, it will be a
lot cheaper than losing Cannas etc. Worth a try, I think.

Most definitely.

--
Kay