Given my lack of space on the roof terrace and the problems with watering, the natural step up is to get an allotment, this is harder than you would think.
There are no allotments available in the borough of Merton, the waiting lists range from 4 months to 10 years. The ones closest to me are 2 - 3 year waiting lists. I’m thinking of trying to find someone to share with, someone who needs a hand in exchange for a bit of space. Will keep you posted.