Day 9: the first three to four centimetres of soil were dry, so I watered until saturation point: it drank 4.5 litres of water.
Day 11: I found an insect on the leaves, which had holes; I then sprayed the plant with soft potassium soap.
The plant is growing well, although perhaps a little poorly: it could be the good weather that is slow in coming.
@CanuckTaughtMe,
thanks for the vote of confidence, but I don't think I'm a good example: it's the first time I've reached the fourth week of cultivation and I'm making a lot of mistakes...