Thin fruit tees in early spring, within about 6 weeks of when the tree is in full bloom or when the fruit is about the size of a marble (half-inch diameter).
How
Remove unwanted fruit by gently twisting or pinching it off the tree, taking care not to break branches or disturb the “keeper” fruit in the process. You can also use small clean pruning snips if needed, particularly for tougher stems like apples or pears.
Remove the smallest or damaged fruits and keep the largest, most healthy-looking ones.
Spacing
Thin apples to one (or maybe two) fruit per cluster, spaced about 6 inches apart on the branch.
Peaches and nectarines should be thinned down to 6 inches apart on the branch. Focus on removing clusters and “twin” fruit that often develop.
Apricots can be left to grow slightly closer together, with one fruit every 3 to 5 inches.
Plums and pluots: Thin to one fruit every 4 to 6 inches for Japanese plum varieties, and every 2 to 3 inches for European plum trees.
Pears don't always need thinning but if crowding, fruit drop, or biennial bearing becomes an issue, thin pears to one or two fruits per cluster, spaced every 6 inches.
Persimmons also rarely need thinning, but it can be helpful for young trees or heavy-bearing varieties like Fuyu. Thin to one fruit every 6 inches.
Loquats don’t need to be thinned, though the fruit size and quality will be significantly improved with thinning on heavy fruit set years. Thin loquats by removing about half of the immature fruits, either by pruning off individual fruit or entire clusters.
Fruit trees that don’t need to be thinned include: avocado, citrus, cherry, fig, pomegranate, mulberry, papaya, mango, banana, guava, or most nut trees. Kiwi vines, blueberry bushes, and bramble or cane berries (blackberries and raspberries) also do not typically require thinning.
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