Lemons are a citrus variety indigenous to the Mediterranean Basin and the Middle East. Under favorable climatic conditions, lemons are inclined to flower and bear fruit throughout the year – these are known as everblooming cultivars. Lemon trees in the south region of Iran usually bloom in April and reach maturation between October to January, depending on the variety. Lemons are commonly categorized in three groups: sour, sweet and other. Commercially grown varieties belong to the sour lemon group.