Summers Care of Fruit Trees

Your main task in the summer orchard is picking and eating all of the delicious fruit your trees produce. There are, however, a few other activities you need to complete to ensure that your trees stay healthy and productive this year, next year and for many years in the future. These include:

• Irrigation
• Summer pruning
• Regular inspections and pest control

Irrigation

The heat and low humidity of a California summer mean that your trees will need to be irrigated to replace the water lost to evaporation and transpiration, the natural process by which a tree loses water through the pores of its leaves. Together, these are referred to as evapotranspiration (ET). Irrigation can be a complex topic. This short article will be able to only touch the surface.

The fundamental questions are how much water to apply and how often to apply it. To answer these questions you need to know three things and perform some calculations: soil type, how much water is lost through ET, and how much water your irrigation system is delivering.

A simpler approach, which is generally adequate for the home orchard, is to refer to a chart that has done the calculations for you. Such a chart is available in the UC publication Home Orchard. As an example, according to the chart, a 15-foot diameter tree growing in an inland area requires a surprising 47 gallons of water per day in June, July and August. This is a starting point. If your tree is in shade part of the day, it may require less water. If it is mulched, it may also require less water. If it is over pavement or receives reflected heat from a building, it may require more water.

Summer Pruning

Many people with a home orchard prune only in the winter. Pruning in the summer, if done correctly, has many benefits and will not harm the tree.

Summer pruning will tend to slow a tree’s growth whereas winter pruning encourages growth. Because many fruit trees actually grow too vigorously, especially the stone fruits such as peaches and plums, summer pruning can be beneficial.

Summer pruning should remove branches that are:

• Dead
• Rubbing on each other
• Water sprouts
• Excessively shading the interior of the tree.
   

If the interior receives too much shade, the buds needed to produce fruit the following year will not develop properly. You do, however, want to leave enough foliage to shade the interior branches during the hottest part of the day.

It is also a good practice to paint the tops of interior limbs with whitewash or white interior latex paint thinned 50/50 with water once you have finished the pruning.

Regular Inspections and Pest Control

There is a Chinese saying that “the best fertilizer is the gardener’s shadow.” The same is true for your home orchard. Regular inspection of your trees to determine whether there is a pest problem or nutritional deficiency will allow you to address these issues before they become bigger.

If you see unusual critters on the leaves or branches, leaves discoloring or wilting on some or all of the branches or dead or dying branches, it is best to figure out what the problem is early.

You can seal an affected branch in a plastic bag and take it in to your local nursery or to your Master Gardeners during office hours. Early identification of the problem can allow for easier and less toxic control.

Now, get ready to eat and share all of the fruit you are going to grow this year and for years to come!!

References

The Home Orchard, Growing Your Own Deciduous Fruit and Nut Trees, Ingels, Geisel and Norton Technical Eds., University of California Agriculture and natural Resources Publication 3485, 2007
Updated edition: The Home Orchard

A Guide to home Orcharding for the Sierra Nevada Foothills, Garth E. Veerkamp University of California Cooperative Extension Publication 31-701, 2001

Micro-Irrigation of Trees and Vines, Schwankl, Hanson and Prichard, Univ. of Calif. Irrigation Program, 1996

UCANR Integrated Pest Management