The lemon tree comes from a tropical and sub-tropical environment, thats why it needs to grow in a warm but sufficiently wet climate, with mild winters and not so wide ranges of temperature.
For the lemon tree the best temperature to grow and vegetate is between 13° and 30° C. A temperature lower than 0° C damages the plants; moreover, if the temperature is higher than 38° and there is no humidity during the ripening setting (when the fruit starts to develop), the growth of the lemon fruit can be compromised. Even a strong wind can be extremely harmful for the lemon tree: the leaves and the sprouts could break off the tree, the branches could break and the fruit could be severely damaged by the rubbing. Rain should not be more than 1800 mm.
In regions where the climate is colder they grow lemon trees with an ornamental aim, in special hothouses (the lemon-orchards) which get opened only during the summer months.
The water to hose plants can be sweetened by putting in every litre the skin of a lemon cut in little strips, and leaving it there for a couple of days.