PICA, Chile — Literally drop by drop, an innovative irrigation technique is turning dry desert into emerald-green farmland producing avocados, asparagus and grapefruit the size of bowling balls.
Agricultural experts say the government-financed project has major potential for creating jobs and bringing much-needed export earnings to this heavily indebted nation.
The center of the project is Esmeralda, a 2,500-acre experimental farm near this town in the heart of the Atacama Desert, 1,100 miles north of Santiago.
Esmeralda is producing a variety of fruits and vegetables at a commercial scale, said agronomist Jorge Olave, who has managed the farm for six years.
Researchers at the farm have conquered the rainless climate through a technique known as "drip irrigation."
"We use the little underground water available, and take it through plastic hoses to each tree or plant," Olave said.
A network of black plastic hoses crisscrosses Esmeralda's sandy ground, carrying water to every plant and tree. Irrigation is done at fixed hours, from two small "drippers" installed next to each plant, Olave said.
The technique, adapted from Israeli methods, has been dubbed in Spanish gota a gota --drop by drop.
It requires a little more water than in conventional agricultural zones, Olave said, "but the yield is far superior here, partly thanks to a more intense sun during longer hours in the day."
He said each grapefruit tree produces about 600 pounds, and each acre can support about 100 trees. He showed a visitor huge grapefruit weighing up to 1 1/2 pounds.
Each acre of tomatoes supports about 20,000 plants and produces 40 tons, a yield almost twice as high as in traditional tomato-producing zones in central Chile, he said.
The Esmeralda plantation also produces oranges, mangoes, lemons, asparagus, apples, peaches and avocados, and will soon begin producing kiwi, pears, watermelon, pepper and artichokes.
"The main thing is that we have proved that this can be done almost everywhere in the desert," Olave said. "In fact, the system is already successfully working at a number of small farms in this area."
Just a few miles away, for example, another plantation, the Matilla farm, spreads bright green over the gray desert.
Geographers say the Atacama receives less rain than any desert in the world. The Guinness Book of World Records describes a spot 200 miles south of here as the driest on Earth. But about 150,000 desert acres have already been identified as potentially high-yielding agricultural land, Olave said, and the total eventually will be substantially more.
The state-run Esmeralda project, whose final stage began in 1981, is financed by the government's Development Corp. with an annual budget of about $90,000.
Hot to Cold
Hugo Rossi, a Santiago agronomist working on the project, said that weather conditions are favorable to the growth of tropical fruits, which cannot be cultivated in other parts of Chile. Temperatures average 95 degrees Fahrenheit here in the daytime and drop to near freezing overnight. Relative humidity is about 10%.
Olave said experts have concluded that small agricultural patches of 10 acres are economically viable in the desert. Under similar conditions in Israel, 7 1/2-acre farms have proved efficient, he said.
The project's next step is to transfer the technology to private landowners. A recent auction of government land in the area attracted more potential buyers than the land available, Olave said.
Starting a 10-acre farm is estimated to cost only $7,000, including purchase of the land.
"The most expensive part is the installation of the drip irrigation system, but then that's virtually a one-time expense," Olave said. He said the plastic hoses last at least 10 years.
The system's efficiency "is beyond doubt now," he said. "Two Israeli experts who visited here recently were impressed with what we have done."