Very often, a apple, pear and plum tree, will lose many of its fruitlets - young fruits - in mid-summer for no apparent reason. Why is this?
The answer is quite simple and basic.
Especially after a good show of flower in the spring, and a good pollination, resulting in many fruits setting, the fruit tree decides that it cannot cope with the huge crop it now has to play mother to! The easy answer - in nature - is to get rid of the problem. The Apple tree - or Pear or Plum tree - simply drops the excess fruit in order that the remaining apples pears or plums can survive and develop into healthy fruits.
Some notoriously good croppers - such as the James Grieve Apple - carry out this 'cull' in early summer, but all trees will do it if there is a perceived threat to their future.
In real nature, the fruit tree needs healthy fruit, which will then produce healthy seeds and therefore potentially healthy, strong offspring. Clever things aren't they!
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By David Hughes