The standard advice from the experts once again doesn’t align with my experience. This time it relates to the idea that thinning fruit will lead to larger fruit. From the horse’s mouth: “Thinning immature fruit at the appropriate time allows each remaining fruit to develop to its maximum size.”
Why? “Excessive fruit compete with each other for carbohydrates and remain small.”
Therefore, “All stone fruits (peaches, apricots, nectarines, cherries, plums, etc. ) require thinning.”
The horse is the University of California publication “Fruit Trees: Thinning Young Fruit.”
Until I learn otherwise, I follow the advice of the experts. So last year I thinned my apricot fruit precisely as they advised. The harvest was very satisfactory. But this year, just as an experiment, I didn’t thin. I wanted to see if the fruit would end up smaller at harvest time. The tree set a ton of fruit, more fruit than last year, but still I left them all, except for some fruit that weighed down the ends of a couple of thin branches and threatened to break them. The result? More fruit than my family and friends could eat, so many that I dried dozens of them, and yet they were the same size as last year. There was no difference in the size of the fruit at all.
My conclusion is that while there are other good reasons to thin fruit, the goal of increasing fruit size is not one of them — for Blenheim apricots anyway.
Thin fruit if they might break a small branch, thin fruit that are diseased or damaged, thin fruit that are too exposed to the sun, for example. But don’t thin fruit thinking that it is the way for “each remaining fruit to develop to its maximum size.”