To test the theory, the Mail bought coriander and basil potted herbs from Tesco, Asda, Morrisons, Sainsbury's and Waitrose and cared for them according to the package instructions for a week.

There is one exception though, coriander which doesn’t like being re-potted (more on that later). Interestingly, all potted herbs need the same amount of sun exposure and watering. This is due ...