On Channel 4 last year (I've only just found it on 4OD - 6 episodes)
Found this to be pretty good, really rate Monty Don and his 'say it as it is' attitude. Some stereotypical Londoner's on the show, my favourite being kierty, the asian lady who said "eurgh, those prickly things" whilst showing Monty around her holding.
They are doing another show (and even invite people who may wish to appear on the next series to apply via the website).
Enjoy,
John