Cultivation Information

History of Olive Production

Olive farming is an ancient pursuit dating back to biblical times. Olive trees, fruit and oil have played important roles in Middle Eastern, Greek, Roman and European cultures for centuries. Originating in the Middle East, olive production quickly expanded throughout the Mediterranean region, finding particularly adaptive conditions in Italy and Spain. The Spanish brought the crop to North America, planting trees in Mexico and California where conditions most closely matched European olive terrains.

From there, growers spread into other regions, including Texas. Olive trees have been growing in the Lone Star State since the 1930s, but it wasn’t until the late 20th century that Texans began to view olive oil as a commercially viable crop. The Texas Olive Oil Council was founded in 1994 to provide information and assistance to individuals interested in successfully cultivating olives in Texas. Today, olive oil is being produced in South, Central and East Texas, and experimentation continues into finding appropriate growing regions within the state.

Olive Growing Basics

 

Studies by extension horticulturists at Texas A&M University have concluded that certain regions within the Lone Star State (primarily South, East and Central Texas) are suitable for olive production.

Climate: Temperature variation in Texas makes olive production challenging in much of the state. To thrive, olives require warm nights and cool days Growth starts in the spring when mean temperatures reach 70 degrees F and continues until the temperatures drop below 70 degrees F in the fall. Freezing temperatures are dangerous to olive orchards, and trees can be killed to the ground at a temperature of 10 degrees F. (A mature tree may regrow from its underground parts even after freezing.) Olive oil production is taking place in South, Central and East Texas, but growers should keep in mind the potential for freezing conditions in a given year.

Botanical Information: Olive trees are subtropical evergreens or shrubs that, in the Mediterranean, are known to live for more than a thousand years. The tree will begin to bear fruit about five years of age. Two types of flowers—perfect and staminate—grow on the tree. Staminate flowers contain only male parts and only perfect flowers will become fruit. Olive trees, in most cases, are self-fertile though production may improve with cross-pollination. Olives fresh from the tree are inedible and must be processed to be served as food or prepared as an oil.

Propagation: Olives are easily propagated and the trees are generally grown from their own roots. Asexual propagation comes from leafy cuttings, from stem cuttings (truncheons), from knotty growths (ovules) or from suckers. When using leafy cuttings, allow six to eight weeks for roots to form. Cuttings may be potted at 10 to 12 weeks, then transferred to a nursery the following spring.

Soils: The olive is adaptable to a wide variety of soils. They have shallow root systems but the soil should be well-drained.

Water: Olive trees are drought tolerant but sufficient watering is ideal. Avoid over-watering. Plant in a sunny, well-drained location.

Nutrients: Olive trees can draw most of the nutrients they need from the soil but usually require nitrogen. Apply one-half to two pounds of nitrogen per year. Fertilize in December and in the spring.

Training: The tree should be trained to three or four main scaffold branches beginning when the plant is three-feet tall.

Pruning: Delay pruning until early spring to avoid late freezes that might damage the tree. Do not top but thin out dead or unproductive wood.

Cultural Practices: To protect from the cold, mound trees with about 18 inches of soil on the trunk until they reach the age of five. Soil should be mounded in November and removed in late March. Cover the foliage when temperatures are expected to drop below 17 degrees F.

 

Growers Notes, Articles, and Tips

 

Growing Olives in Texas

 

This presentation by Nasir S. A. Malik (Plant Physiologist) includes 70 slides. A high-speed connection is recommended. The presentation is a PDF document file. You can download the AdobeReader® for free if it is not installed on your computer.

Because of the large file size, the presentation has been separated into 5 parts for quicker download.

Part 1 - Mostly documents experimentation on affect of seasonal temperatures on olive tree flowering but does touch on 2004 data for EVOO consumption in US.

Part 2 - Comparisons of Open field temperatures in Galveston, Sea Drift and Orange to Wet tent experimental temperatures. Photos of flowering and fruiting Arbequina trees in Galveston.

Part 3 - Photos of Texas Olive Oil Arbequina harvest in Carrizo Springs in 2007 which resulted in thousands of gallons of EVOO.

Part 4 - Photos of equipment and extraction process at Texas Olive Ranch.

Part 5 - Experimental methods for olive propagation.

 

Soil and Water Testing

 

Before you plant your trees, have you tested your soil and water?

We at the Texas Olive Oil Council think it's a vital step before your first planting. We recommend A&L Plains Agricultural Laboratory in Lubbock, Texas. Ask for a package to test the soil and water. When submitting the samples, ask for a texture analysis on the soil, and the "SAR" or sodium absorption ratio on the water. The ideal texture for growing olive trees is a well drained soil with no more than 20% Clay, 40% Limestone, 40% Sand. (Olive trees don't like wet feet)

You may reach the Lab at (806) 763-4278.

 

Fertilising - Soil Fertilising & Foliar Fertilising

 
Soil Fertilising - On the soil, per year, mature tree
Fertiliser Kg/tree Pound/tree
Urea 0.5 1
Calcium Nitrate 0.5 1
Mineral Superphosphate 0.5 1
Potassic Sulphate with Magnesium 0.65 1.3

These doses must be distributed in two times:

  • the first - two weeks before the beginning of the growing
  • the second - two weeks before the blooming


Foliar Fertilising - Never during the hot hours of the day
Timetable Quantities x 25 gallons
Beginning of the growing
Urea 4.5 pounds
Boron 2 ounces
Liquid organic fertilizer 0.15 gallons
Adhesive - Wetting 0.015 gallons
Three weeks before the blooming
Same as above
Three weeks later the blooming
Same as above
At the hardening of the stone
Potassium Phosphate, monobasic 2.2 pounds
Liquid organic fertilizer 0.15 gallons
Adhesive - Wetting 0.015 gallons
A2.5 Four weeks later
Same as above

Use a minimum of 40 gallons per acre. In case of spray with atomizer, multiply the doses three times. If during the growing season, insects are present.

 

Fall Suggestions

 
  1. Stop the addition of nitrogen each year at mid-July, so that tree growth will not accelerate.
  2. Stop all irrigation October 1, to slow vegetative growth.
 

The Texas Horticulturist

 
The Olive: This adaptable tree offers future possibilities for Texas.

A tree which can help celebrate both the past and the future of Texas is the olive. Along with the oak, the olive has appeared on the seal of Texas from the days of the Republic till now. The oak represents strength, the olive represents peace and security.







 
 

Olive Tree Sources

 

California Olive Oil Council

Provides a list of olive tree growers in California

Texas Olive Ranch

Jim Henry sells all varieties of olive trees from 4" to 20 gallon. Contact Jim Henry by phone at 214-325-5787 or email olivehenry@aol.com.

 

Book Recommendations

 

UC Davis releases organic olive oil production manual

Organic Olive Production Manual provides detailed information for growers on production issues, economics, pest control, harvest, and organic certification and registration. The 112-page publication includes 45 photographs. The manual, ANR Publication 3505, may be ordered from the UC ANR Publications Web site at http://anrcatalog.ucdavis.edu. The cost is $18. The manual was developed as a supplement to ANR's Olive Production Manual, 2nd Edition, (ANR Publication 3353).

Pruning and Training Systems for Modern Olive Growing

We recommend this important book to growers and potential growers. Authors by Ricardo Gucci and Claudio Cantini. ISBNO 643-064435.

 

Olive Oil Resources >>