why won't my apples redden?, page-2

Fruit trees such as apple by nature need a lot of nourishment in the form of fertilizers, if they are smaller than most others in your back yard, it will produce fruit but you will find they won't ripen because the tree throws it's nourishment back into the plant and the fruit sort of just stops in mid ripening.

But the fruit will be fine to eat if picked and left in a plate for a week.

Nothing like home grown produce.