Last Sunday's "Broadcasting House" on BBC Radio 4 included a piece which mentions (in passing) Honor Oak's "One Tree Hill Allotment Society" and interviews the vice-chair.

You can listen to it (until next Sunday) via the BH website - http://www.bbc.co.uk/radio4/news/bh/ - click on "listen to the latest edition". Skip to 23 minutes and 55 seconds for the relevant section - it lasts about 8 minutes.

It's more about local veg, bartering and allotments than Honor Oak but interesting nonetheless.