Illustrated manuscripts & early depictions of landscapes in portrayals of Biblical gardens give us a glimpse of gardens - real, symbolic, familiar, & imagined by artists & their clients during those periods.
In Latin, the word for apple and the word for evil, malum, are identical. Christain tradition has it that the Tree of Knowledge in the Garden of Eden, the fruit of which Adam and Eve were forbidden to eat, was an apple tree [Genesis 3:3]. In pictures of the tempting of Eve by the serpent in the Garden of Eden, Eve is often shown with an apple her hand, offering it to Adam. The apple may also be symbolic of Christ, the new Adam, who took upon Himself the burden man's sin. For this reason, when the apple appears in the hands of Adam it means sin, but when it is in the hands of Christ, it symbolizes the fruit of salvation. Such interpretation is based upon Canticles 2:3, "As the apple tree among the trees of wood, so is My beloved among the sons." As Christ is the new Adam, so, in tradition, the Virgin Mary is considered to be the new Eve, and, for this reason, an apple in the hands of Mary or Mary sitting under an apple tree is also considered an allusion to salvation.