Apples blossom from early spring to late summer, depending on the variety. In order for the apple blossoms to fruit, they need to be pollinated. While apples can sometimes self-pollinate, in most cases better fruit form when trees cross pollinate. Bees are an integral part of this process and are prized by orchardists for the service they provide. Apple blossoms typically range from white to a dark pink, depending on the variety.
In late spring, after the blossoms are pollinated, the petals drop off and a small apple begins to form. The apples grow throughout the summer. During the last few weeks before harvest the cells in the fruit swell with water and starch is converted to sugar. The chemical that causes the astringent taste of unripe apples is absorbed. Air spaces develop between the cells; some varieties have more air spaces than others. Those with a lot of air spaces have white flesh, those with more densely packed cells have a yellowish flesh.