Pare the pear tree: Too much is more than enough
Remember about five or six months ago when you pruned your fruit trees, then a couple of months later fertilized them.
Approximately six weeks ago you were admiring the beautiful blossoms on those fruit trees. Guess what? I can almost guarantee that you have too much fruit on those limbs.
Allowing too much fruit to ripen on your trees is detrimental in more than one way. Your fruit will be small, deformed, and definitely lack that sweet flavor your have been yearning for, if you do not remove part of them.
Yes, I understand it is a hard thing to do, even for me. But culling (removal of excess fruit) from our trees is a necessity. A tree's leaves supply energy for growth; if there are not enough leaves on the tree to support the number of fruit that has set, the fruit will compete with each other for carbohydrates and remain small. Too much fruit on the tree can also lead to limb breakage, even with light winds.
Ask yourself, do we have any wind in Kingman? Even if the limbs are not broken, they most likely will become bent or twisted from the weight of the fruit, creating a pruning problem later.
Thinning fruit can also reduce the spread of some diseases. Where two fruits are touching on the tree, moisture is trapped between them, providing good conditions for disease development. Diseases such as brown rot can quickly spread from one fruit to another just before harvest. Air movement around separated fruit is greater, which means that the surface of thinned fruit dries more quickly, reducing the chances for the spread of disease organisms. Certain insect pests, such as leaf rollers, prefer to feed in fruit clusters.
Thinning prevents biennial fruit production. Biennial fruit production is when a tree produces a heavy fruit crop one year and a light crop or no crop the next year. This usually occurs with apples and pears, especially so for dwarf varieties. Blossom thinning or thinning young fruits is the best way to avoid alternate bearing years. Waiting until midsummer is too late to affect next year's crop, since the time has passed when next years' blossom buds are initiated.
In some cases flowers and fruits naturally thin themselves. This usually happens in April or May, and is referred to as June drop. I know I said April or May, then called it June drop, but I had nothing to do with the naming of the occurrence.
Some types of fruits and nuts naturally thin themselves, such as cherries, figs, pomegranates, citrus and most nut trees. Stone fruits such as peaches, nectarines, apricots, and plums require thinning, as do pome fruits such as apples, Asian pears and European pears. Thinning can be done any time after blossoming, however it is a good idea to wait and see if there is any natural fruit drop.
May is a good month to thin fruit. Stone fruit (peaches, nectarines and apricots) will be about three-quarters to one inch in diameter and pome fruit (apples and pears) will be a half-inch to one inch in diameter. Remove all twins (two fruits grown together like Siamese twins) on all trees. Neither fruit will develop properly.
How much do I thin?
Peaches and Nectarines: For peaches and nectarines, leave no more than two fruits on a hanger (small branch). On larger branches, thin fruit leaving three- to five-inch spacing between fruit.
Plums and Apricots: Plums and apricots are generally heavy fruit setters, requiring more thinning. Always save the largest ones, and space the remaining fruits three to fours inches apart.
Apples and Pears: The pome fruits have two main differences from the stone fruits. The fruit is produced on spurs and the flowers set in clusters of five, with the bloom in the center known as the "king blossom." Thin to one or two fruits per cluster, leaving the king blossom fruit as it will be the largest. Space fruit six to eight inches apart regardless of spur placement on the limb. It is important to know that all spurs may not produce fruit in consecutive years. So, thin to eliminate all flowers and small fruit on every other spur.
This needs to be done on apple and pear trees 30 days after bloom or the thinning will not be effective in reducing biennial fruit production. It is also worth noting that with Asian pears, it is more beneficial to remove excess blossoms before fruit sets.
As mentioned before, cherries, figs, pomegranates, citrus and nut trees do not usually require thinning. However, the branches of all trees can break from excess weight, so thinning may be beneficial.
It is not recommended to allow fruit to set on trees until they are four year old. Allow the tree to become well established with strong limbs before allowing fruit production.
Nothing tastes better than a piece of fresh fruit ripened on the tree. So thin those trees for the best quality and flavor. Your tree will thank you.