Source: PhotoFunia
Image: PhotoFunia
The trees in the foreground of our cover to the right are palms, but those in the background are olive trees, a truly incredible resource.
Source: flickr
Image: avlxyz
The olive tree can be grown for personal consumption or as a product to supplement income, as its fruit has grown into a modern industry worth an estimated $20 billion a year. In 1991 Australia imported $38 million worth of olive products, and by 1996 imports rose to $115 million. Olive oil now commands up to 50 percent of the edible oil shelf space in leading supermarkets. Japan's imports of olive oil almost doubled from 1995 to 1996, and the US imports 100 times the olive oil locally produced. Taiwan, Malaysia, Singapore and many northern European countries are also rapidly increasing their demand for high quality olive products.
Source: flickr
Image: andrea.pacelli
The olive is a beautiful tree with silvery grey-green leaves, and the ability to withstand the battering of storms, salt water, heat and cold, and remain "evergreen". The olive is a drought resilient tree, and unlike many other fruit orchards, an olive grove can be neglected and then revitalized to be brought back into production.
Ancient olive trees in Gethsemane in Jerusalem
Source: flickr
Image: Ian W Scott
With minimal care olive trees will live and produce fruit for well over a thousand years; this has been demonstrated in the Middle East and places like the Garden of Gethsemane in Jerusalem. There are no limits to the commercial viability of an olive grove on fertile soils, provided that the tree receives suitable annual pruning, water and fertilizer; a well-maintained orchard planted with 5 meter by 8 meter spacing can be commercially viable for well over 100 years.
Olives are regularly grown on properties throughout the world as a handsome windbreak; spacing in this case can be as close as three meters (10 feet); however this spacing will not be as productive per tree. Olive groves, avenues and boundary plantings increase the value of any property.
Source: flickr
Image: Jon Shave
Olive trees will tolerate a large range of soil conditions, preferring a neutral to alkaline (having a pH greater than 7) soil type. If your soils are acidic, they may be easily changed to an optimal pH of 7.0-8.0 by simple methods such as the addition of agricultural lime, a soil additive made from pulverized limestone or chaalk. Olives will often grow in hilly, rocky areas that are not suitable for other crops.
However, they do not like very heavy soils that hold excessive water after wet periods. Therefore the olive may not be the best tree in flood prone areas. Olive trees are best grown in areas with cool to cold winters and hot summers; for many varieties some winter frost is preferred. A frost is a deposit of small white ice crystals formed when the temperature falls below freezing. Summer temperatures are important for the growth of fruit-bearing foliage. Most olive growing regions of the world have average maximum daily temperatures, in the hottest month of summer, somewhere above 30 degrees Celsius/86 degrees Fahrenheit. However, apart from the cool winter and warm summer requirements, the moisture levels of the tree must also be adequate. Some varieties have been seen to survive minus 15 degrees Celsius/5 degrees Fahrenheit as long as they are in good health. A properly irrigated grove will withstand much greater extremes in temperatures than a traditionally planted dry land grove.
Lovedale Hunter Valley
Source: flickr
Image: Kyle and his Nikon
The main factor in choosing spacing is the harvesting method to be employed on the grove. In the majority of groves, the best yield per hectare over a thirty year period results when trees are planted 5 meters apart in hedges, with a space of 8 meters between the hedge rows. This spacing yields 250 trees per hectare (104 trees/acre). With densities greater than 200 trees/ha (hedge planting), it is important to run the hedge rows approximately north/south so that the sun penetrates the foliage of all trees in the hedge most effectively.
Olive trees need very little water to survive if serving as an ornamental or landscape tree. However, for a good crop, mature olives generally need at least two waterings to field capacity (full depth of roots - approximately one meter in mature trees), each winter (this will depend on soil type). A drastic reduction in rainfall and irrigation water will result in a poor crop of only one-third to one-half of a fully irrigated commercial crop. A mature olive grove will use between 6 and 10 mega-liters of water per hectare per year. For this reason fertigation (the use of fertilizers through an irrigation system) should be employed, as it is a very efficient way to irrigate and will produce an abundant crop.
Gray water rain collection
Source: flickr
Image: kingey1971
The olive tree is one of the few fruit bearing trees that will survive and still produce quite well with poor quality saline (salty) water. Saline water that is unfit for human use is generally quite suitable for olives. For this reason olive trees can be watered with the grey water or rainwater harvested in the Riba City Model.
Olives can be marketed in a wide selection of products and packaging, and include the following: green or black plain, herbed, stuffed, or sliced pickled olives, in bottles, cans or vacuum packaging. Olives can be processed using many different recipes, each producing unique flavors. Olive oils are processed and sold in many different grades in bottles, pressure packs or cans.
Source: flickr
Image: A. La Vita
Olive oil is also used in soaps and oils; the Japanese are using olive oil in a wide range of cosmetics, shampoos, conditioners and health products. Olive Leaf Extract is proven to be anti-bacterial, anti-viral and anti-fungal. Olive by-products such as olive seeds are being used to produce electricity, fertilizers, stock feeds, activated carbon, and even plastics. Olive waste could be used in the combined heating and power system on-site as well.
Source: flickr
Image: savor_soaps
