Caroline O'Donoghue: Ten thoughts on being asked to 'plant-sit'

I was left with very specific instructions, along with a colour-coded plan of her yard to indicate which plants needed a can, half a can, or two cans of water.
I do not garden, so I can only presume that my friend cycled through her more green-thumbed neighbours before eventually asking me to water her plants while she’s on holidays.
In her South London yard she has tomatoes, courgettes, carrots, beetroot, lettuce, and beans.