Gardening can be viewed as a largely pointless hobby, but the evangelical zeal and camaraderie it generates is unique. Charlotte Mendelson is perhaps unusually passionate about it. For despite her superficially normal existence, despite the fact that she has only six square metres of grotty urban soil and a few pots, she has a secret life. She is an extreme gardener, an obsessive, an addict. And like all addicts, she wants to spread the joy. Her garden may look like a nasty drunk old man's mini-allotment, chaotic, virtually flowerless, with weird recycling and nowhere to sit. When honoured friends are shown it, they tend to laugh. However, it is actually a tiny jungle, a minuscule farm, a wildly uneconomical experiment in intensive edible cultivation, on which she grows a taste of perhaps a hundred kinds of delicious fruits and odd vegetables. It is a source of infinite happiness and deep peace. It looks completely bonkers. Arguably, it's the most expensive, time-consuming, undecorative and self-indulgent way to grow a salad ever invented, but when tired or sad or cross it never fails to delight.