In summer, small, weak fruit may drop off trees

SMALL, UNRIPE APple fruits are dropping from my trees. I have watched the development of these fruits with a close eye right from the time the trees blossomed. At that time, frosty nights threatening to kill the blossoms had me gnawing at my fingernails. Many times since bloom, I have donned raincoat, goggles and gloves and sprayed an organic insecticide (“Surround,” made from kaolin clay) to protect the developing fruits from inevitable insect attack.

The dropping fruits make me a bit nervous, but I know there is a rationale to this seemingly ungrateful behavior. The goal of any fruit tree is to produce and disperse seeds, and luscious fruits are a good way to attract animals for this job. Since so many ills can befall tender blossoms and temperamental young fruits in early spring, more fruits initially develop than the tree has energy to bring to full ripeness.

Remember all those blossoms in the spring? Only 4% of the blossoms on an apple tree are needed for a full crop of fruit.

As the season progresses and a tree becomes more confident of having nurtured an adequate number of fruits through critical periods of frost, insects, and diseases, excess fruits are naturally shed. The first fruits to go are the weakest: those that were poorly pollinated or damaged by pests.

This shedding of fruits doesn’t occur in one fell swoop, but in successive waves. Most of us hardly noticed or were bothered by the initial shedding of pea-sized and smaller fruits right after bloom. But the “June drop” of bona fide, albeit still relatively small, fruits is very obvious.

Those fruitlets lying on the ground can be disconcerting, but I just keep reminding myself about why they are there, then gain further reassurance by glancing up at all the branches still laden with fruit.

Those fruitful branches also remind me that I am going to have to hand-pluck even more fruits off as soon as the tree has shed all that it thought were adequate. Remember, the tree is planning to ripen enough fruit for a good crop of seeds. But I don’t care about seeds; I want large, sweet, juicy fruits. The way to get large, sweet, juicy fruits is to channel a tree’s energy into fewer, but consequently higher quality, fruits.

As soon as June drop has run its course is the time to thin fruits on apple trees, as well as on peach and Japanese plum trees. The rule of thumb is to leave a few inches between each fruit. Apricots and European plums need thinning only if the branches are weighted down with an extremely heavy crop a matter of judgment and guts for the gardener. Cherries don’t need thinning. When hand thinning, do just as the tree did: remove weak and pest-damaged fruits first.

Any gardening questions? Email them to me at garden@ leereich.com and I’ll try answering them directly or in this column. Come visit my garden at www.leereich.com/blog.