Fruit Trees

Avocado Persea Americana

San Diego is the ideal place to grow fruit bearing trees, from semi-tropical to temperate, from water thirsty, if you can afford the water, to low water.  Citrus grows here as do stone fruit.  Not only do the more common fruit trees like citrus, peaches, apples, plums and apricots grow here, but more exotic fruits like loquats, sapotes, avocados, cherimoya, macadamias, mango and olive also grow here.  Pomegranates and figs are ideally suited for our climate.

The California Rare Fruit Grower (CRFG), San Diego Chapter has monthly meetings where experienced and novice tree growers meet to discuss topics of interest, share fruit samples, and exchange ideas.  The state organization published a Fruit Facts on their web site that describes in detail common and unusual fruit with their description, culture and taste characteristics.  The data for each fruit also lists varieties or cultivars.

Most homeowners are attracted to common fruit trees, like peaches, plums, apples and apricots, as evidenced by their availability in nurseries.  The exotics take a little hunting.  The common fruit trees that are deciduous, that is, they lose their leaves and go dormant, are usually available in very late December or early January as bare root.  Because they are dormant, they can survive for while with out soil around their roots.  They are thus easier to ship, care for, and plant.

To successfully grow one of the common deciduous trees, attention needs to paid to a couple of details.  For fruits trees to successfully produce most require a certain number of hours of cold temperatures before they will bear.  This is called the chill hour and it is an annual requirement.  Chill hours vary by region and area in San Diego.  Expect more chill hours in Julian than Coronado.  A broad definition and a table of values for California has been compiled by the University of California Agricultural and Natural Resources Department.  Once the number of chill hours has been found for your area, choose a variety of your desired fruit tree that will requires those chill hours or less.  The Dave Wilson Nursery website also had information about tree planting. For fruit tree growers the site has details about chill hours.

Most fruit has a short interval where the fruit is optimal for harvest.  But, varieties are often available with different interval lengths or estimated ripening start days.  Planting varieties of the same type of tree, peach for example, with different ripening times can provide fresh, home grown, peaches over a longer period.  Again the Dave Wilson Nursery has a fruit harvesting chart for those trying to spread out the fruit harvest.

For fruit and nuts other than citrus, the Dave Wilson Nursery has a number of informative videos available on Youtube.  The Backyard Fruit Tree Basics describes how to manage fruit tree and emphasizes the difference between the objectives of a commercial grower and those of a home owner when growing fruit trees.

Citrus is also commonly planted in San Diego.  Although citrus goes dormant in the winter, they never lose their leaves and are commonly planted from pots, rather than bare root.  They can be planted any time, but are best planted in the winter when dormant.  The State of California maintains the Citrus Variety Collection at UC Riverside of over 700 type of citrus trees.  They range from those that are commercially common, like the naval orange, to the unusual, like Buddha's hand, to those that may eventually become commercial, like the seedless kishu mandarin.  Find an available variety at a local nursery, then get the specific details from the Citrus Variety Collection.  Most types of citrus holds well on the tree.  Naval Oranges, for instance, ripen around late January in San Diego but can be eaten (if all are not harvested) until June.  Even choosing citrus of different varieties can extend the harvest.  The Frost Owari Mandarin is ripe from October to December.  The Gold Nugget Mandarin is ripe from February to June.  Both varieties are seedless.  With just those two varieties, mandarins can be eaten from October to June.

Fruit trees hardly every reproduce from the parent tree when planted from seed.  This is one of natures methods of increasing diversity.  As a result, most commercial trees are produced by grafting a desirable piece of the parent tree onto a rootstock.  The variety of the tree is the name of the graft.  The seed from an Elberta peach, for example, may not produce a tree with identical fruit.  However, if a branch from an Elberta peach tree is grafted onto an appropriate rootstock, the fruit will be Elberta peaches.  The rootstock, then, is also quite important.  It can determine the size of the tree, the trees ability to grow in differing soil types, and the trees resistance to soil born illnesses.  Stone fruit can be grafted on to dwarfing rootstock to result in trees that never grow high than 6 feet, but produce more than enough fruit for a family.  Citrus is commonly grafted onto three types of rootstock; standard, which results in trees sometimes up to 25 feet; dwarfing for trees around 14 to 16 feet, and ultra dwarfing for trees less than 8 feet.

Fruit trees can have ornamental value as well.  The Red Baron peach is a mass of double pink flowers in the spring.  Pomegranates have bright orange flowers and leaves with red and green that turn yellow in the fall.  A kumquat at maturity is an attractive deep green with small orange fruit.