The Wealth of Nations by Part 1 Chapter 11 Page 28

profit of insurance. The circumstances of gardeners, generally mean, and always moderate, may satisfy us that their great ingenuity is not commonly over-recompensed. Their delightful art is practised by so many rich people for amusement, that little advantage is to be made by those who practise it for profit; because the persons who should naturally be their best customers supply themselves with all their most precious productions.

The advantage which the landlord derives from such improvements seems at no time to have been greater than what was sufficient to compensate the original expense of making them.

In the ancient husbandry, after the vineyard, a well-watered kitchen garden seems to have been the part of the farm which was supposed to yield the most valuable produce.