Has anyone successfully grown citrus fruit outside in London?
Many sources say that eg. kumquats are hardy down to -10 and kaffir limes to -15 (or more) and so on, but how useful is that information? All of these sources go on to suggest that the trees should nonetheless be brought indoors for winter.
Can anyone add anything to that picture? Can a kumquat live outdoors in London? Or anywhere in the UK? I'd quite like a citrus tree in the garden but am not sure I want one in the house.