Wednesday, April 27, 2011

Fruit Thinning of Apples and Pears

   Tree fruits generally bloom heavily, so some fruits will develop even if some blooms are killed by frost.  When many fruit set, as they did this year, fruit trees naturally shed some of the developing fruit, so the fruit left on the trees will grow better and ripen their seeds.  Most  years, such as this one, fruit growers need to take nature a step further and thin tree fruits, by removing excess fruits while they are still small, so the remaining fruits will get larger and sweeter.
    Apples and pears can be thinned chemically, which saves huge amounts of labor compared to peaches, which must be hand-thinned.  We use a carbaryl spray between 10 and 25 days after full bloom to thin apples and pears.  The pears reached the thinning stage a few days ago.
These young pears are at the stage for fruit thinning.  The thinning sprays will cause some fruit to drop, ideally leaving one fruit per cluster remaining.

   Apples are at the thinning stage now.  We'll apply an apple thinning spray in a few days, whenever the winds calm enough to allow it.
Some of these young apples are developing well, while others are naturally failing to develop and will fall off.  The crop needs further thinning to produce large, sweet fruit.