Thinning

Apples are prone to biennial bearing. If the fruit is not thinned when the tree carries a large crop, it may produce very little flower the following year. Good thinning helps even out the cycle, so that a reasonable crop can be grown every year.

Commercial orchardists practice chemical thinning, which is not practical for home fruit. Apples bear in groups of five (or more rarely six) blossoms. The first blossom to open is called the king bloom. It will produce the best possible apple of the five. If it sets, it tends to suppress setting of the other blossoms, which, if they set anyway, should be removed. The next three blossoms tend to bloom and set simultaneously, therefore there is no dominance. All but one of these should be thinned for best quality. If the final blossom is the only one that sets, the crop will not be as good, but it will help reduce excessive woody growth (suckering) that usually happens when there is no crop.