Graft

Most cultivated citrus trees are propagated by grafting desirable types onto hardy rootstocks. For example popular lemon such as Eureka, which has few thorns, is grafted as a bud onto a thorny wild or rough lemon (all lemons are Citrus limon). For other types of citrus such as grapefruit and orange (C. sinensis), use of the rough lemon or sour orange (C. aurantium) as rootstock has been discontinued in favor of the wild orange (C. trifoliata). As a rootstock the latter species can tolerate wetter conditions than the other stocks, and its use does not diminish the quality of sweet oranges as rootstocks of rough lemon do.