Thinning out fruit trees involves removing some of the crop before it matures. It may seem wasteful to remove and destroy perfectly good fruit, but the reasons behind it are based on sound horticultural practices.
When you remove some of the crop, the remaining fruits will grow larger which means you will have a greater ratio of flesh to pit. Pits will be the same size either way, so bigger fruit means more to eat. The earlier in the season you do the thinning, the bigger the remaining fruit will get. Another reason is to prevent the limbs from breaking due to an extra heavy fruit load.
Fruit buds actually appear the year before the fruit grows and you will remove some of them when you do your normal fall pruning, but that is usually not enough.
Some fruit trees will have different levels of production in alternate years. They will need to be thinned in the years when they have a heavy crop. If you are not sure if your trees do this, contact your local cooperative extension.
Thinning is important for trees with fruit that grows in clusters. It is also important in the development of young trees. While trees are still young and growing, producing fruit can stunt the tree’s growth. IF they are stunted, they will never produce a good crop. On the opposite side of the equation, the fruit size in older trees will be smaller. They need to be thinned even if they have a low to moderate crop. Week trees need to be thinned so they devote their energy to getting better instead of producing fruit.
Fruit clusters should be broken up leaving just one fruit. Space fruit from 6 to 8 inches apart by first removing any damaged or weak fruit by hand once the fruit is about the size of a nickel. Shaking or jarring the limbs will cause fruit to fall off, leaving the strongest on the tree. Then follow up with hand thinning if necessary.
The fruit should always be removed from ornamental trees right after the flowers are done.
This has to be done with fruits that have short stems and grow so close together that they damage each other. Fruits like cherries that grow on long stems will do just fine by themselves as will blue berries, black berries , raspberries and other berries that grow on bushes. If in doubt about what to do, contact you local cooperative extension.
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