Saturday, August 6, 2011


Greenhouses in Southern Spain taken from the Space Station.

The sunny south of Spain offers more to the national economy than simply tourism. Over the past 50 years, the small coastal plain (campo), some 30 kilometers southwest of the city of Almería, has been intensively developed for agriculture. An estimated 20,000 hecatres of extra-early market produce is grown in greenhouses in the Campo de Dalías, and it accounts for over $1.5 billion in economic activity. The area has a dry, mild, Mediterranean climate and is further sheltered on the north by the Sierra de Gador mountains. With just slightly more than 200 millimeters of annual precipitation to support crop growth, the area also relies on groundwater fed by small stream aquifers from the mountains to the north.

This image was taken with a digital camera by the crew of the International Space Station near midday in early February. Note the dense, bright pattern of thousands of greenhouses extending from the shoreline right up to the base of the mountains and even into some of the smaller valleys. Salt pan operations can also be seen in the long coastal lagoons.

Green houses as far as the eye can see around Almeira, Spain. They grow vegetables year round for the European market.

Who will capture first, the potential of the Northern half of Belize? Sugar cane growers and Banco Atlandida, of Honduras, or Belizean Greenhouse growers? THE POTENTIAL GOLD RUSH IN BELIZE IS JUST STARTING! Will need ADDED VALUE processed products and packaging, but export markets are ready and waiting.

10,000 Greenhouses around Almeira, Spain bring properity and lower temperatures than average.

From the lens of a passing satellite, Almería province is one of the most recognisable spots on the planet. The roofs of tens of thousands of closely packed plastic greenhouses form a blanket of mirrored light beaming into space.

The shimmering surface is down to an agricultural gold rush that has turned one of Spain's poorest corners into Europe's largest greenhouse. An area so arid and dusty that it provided the backdrop for spaghetti westerns, Almería has made a fortune by covering itself with a canopy of transparent plastic. Above all, it is a monument to the way we now grow our food. Almería, and the area around it, is Europe's winter market garden, spread across 135 square miles.

Symbols of hastily acquired wealth abound. Farmers glint with gold jewellery. New shopping malls rise above the plastic. Immigrants from as far off as Mali, Colombia or Ukraine offer their toil and their sweat. Instead of trying to sell cars or banks, billboards advertise seeds.

Antonio Moreno, one of thousands of smallholders who have built this plastic jungle, knows how to put fresh tomatoes on British tables in January or courgettes at Christmas. He grows crops that have no direct contact with nature beyond sun, air and water. "You really should wear shorts in here," he says in the 45C (113F) heat as he points to tubes from which tomato plants sprout.

Mr Moreno's plants will never touch soil - they grow from bags filled with oven-puffed grains of white perlite stone. Chemical fertilisers are drip-fed to each plant from four large, computer-controlled vats in a nearby room. He talks proudly of his vats. They hold, he says, potassium nitrate, magnesium and potassium sulphate, calcium nitrate and phosphoric acid. "The plants get exactly what they need, nothing more and nothing less," he says. "There is no waste."


He will crop tomatoes continuously from October to July. The greenhouses are so successful that they have swamped the plain of Dalías, where people such as Mr Moreno's father used money earned in French car factories or Swiss restaurants to buy small plots. Now the sheeting is moving up the valleys of the nearby Alpujarra hills, one of Spain's most bucolic, unspoiled areas. Diggers are also gouging terraces in nearby Granada province.

"They block up dry riverbeds and destroy mountainsides but nobody does anything, however much we complain," says environmentalist Juan Antonio Martínez, surveying the scarred hills at Albuñol. "If there is a serious storm, much of this will be washed away."

A chemical tang hangs in the air along the dried-out bed of the Albuñol, where empty pesticide containers bearing toxic warnings lie among the plastic litter. On the coast at El Pozuelo plastic waste is piled calf-high. "The worst thing is that much of this is done with European Union grants. Money is handed out to young farmers via local authorities who simply ignore the requirement that the environment be respected," he says.

The Alpujarras are the adopted home of many northern Europeans offering esoteric treats such as Buddhist retreats or hikes into the snow-capped Sierra Nevadas. Some in the small, white-painted villages are said to be selling up. "We denounce things to the police but nothing happens. It is chaos," says Gari Amtmann, a long-time German resident in Válor village. "For many people this is all they can do to make money."

There is growing evidence, too, of more serious damage. In his laboratories at San Cecilio University hospital in Granada, Professor Nicolás Olea has detected a link between some pesticides and increased risk of breast cancer in women and testicular problems in boys.

Although Prof Olea has not proved a link, he says the signs for those who work in or live near the greenhouses are too strong to ignore. He points at up to 40kg of pesticide applied per hectare (88lbs per 2.5 acres). "Every time we test the hypothesis, the results point the same way." Pesticide-related residues are now present in umbilical cord blood and placenta. Last month he exposed an increased risk of cryptorchidism (undescended testicles) among boys.

But it may take 20 years to prove cause and effect. That, he says, would be too late. "We do not know what will happen, but we have reasonable doubt."


British supermarkets are secretive about how much produce comes from Almería. Tesco calls this "commercially sensitive information". But Rafael Losilla, editor of a local farming magazine, names Tesco, Waitrose and Sainsbury's as valued customers. "Britain is the third-biggest export market after France and Germany," he says.

Supermarkets said rigorous tests and standards imposed on farmers were in place to prevent goods with excess pesticide residues reaching the shelves. But Prof Olea fears potential dangers are being ignored. "Something may have 10 substances in it that are all at legal levels, but what does the mixture mean? ... Why not measure the combined effect of the cocktail?"

However, he recognises UK consumer power has been an unexpected force for good. In the 1990s, British supermarkets became the first to demand rigorous controls - and pay extra for them. "The British are tough to work with," says farmer Juan Segura, who helps run a farmers' cooperative in San Isidro.

On the packing line here, small boxes of cherry tomatoes bearing Sainsbury's "sweet and juicy" stickers have been kept back for checks. Quality certificates awarded on behalf of Tesco or by Oxfordshire-based CMi certification company are pulled out. "We do not want to lose them as clients. Co-op members have been thrown out for breaking the rules," says Mr Segura. One packer was sacked after her chewing gum was found on an avocado at a French supermarket.

Mr Segura says farmers look for ways to limit pesticide use. "Biological controls" - or getting "good" insects to eat "bad" ones - is the latest solution. But in the driest corner of a country struck by severe drought farmers fret more about water. Drip irrigation may cut waste but aquifers are still drying up. Some are so full of intruding seawater that some crops can no longer be grown.

As problems arise farmers seek scientific fixes. Soon some will not even need rainwater. A desalination plant, turning Mediterranean seawater into freshwater, is set to rescue them. That will leave only the sun and air untouched by the human hand, or machinery, before reaching their plants.

in Almeria, Spain
In Almeria greenhouses stretch from the mountains to the sea!

By Bruce Schundler

Based on a speech givento
The Perlite Institute on May 21, 2000
by Manuel Lucas--Gen'l Manager of Otavi Iberica
see also

In many parts of the world, but especially in the province of Almeria, Spain, hydroponic growing methods have changed the way farmers operate. And in the process, Almeria has been transformed from the poorest province of Spain into one of the ten most affluent!

Growers around the world are trying to grow more fruits and vegetables with less water and less land. And in Almeria, Spain perlite hydroponic systems seem to be helping them do this!

Perlite Grow Bags
Perlite Grow Bags with Six Plants in each Bag"
In Almeria, a beautiful semi-arid area along the Mediterranean, greenhouses currently cover over 30,000 hectares (more than 74,000 acres) of land from the sea to the mountains. Over 2,700,000 metric tons of produce are being grown in the region including lettuce, , cucumbers, watermelons, beans, squash, cucumbers, peppers, and tomatoes.

What makes these numbers particularly interesting is that almost 8 % of all vegetable greenhouses in Spain are now using hydroponic methods, and approximately 54% of Spain's entire hydroponic industry is in Almeria!

When growers and the government first tried to develop this greenhouse industry in the 1980's, a special "system" using sand, manure, clay, and top soil was used. The problem with this "Enarenado system" was that too much water was required and the soil eventually suffered from soil toxicity. Later more sophisticated rock-wool hydroponic systems were introduced in the 1990's, but currently the most popular media is perlite, and it is the media which is growing the most.

There are different growing systems or methods being used in Almeria, but perlite seems to be the most popular. Based on current estimates the different systems break down into the following percentages:

Perlite 36.4 %
Sand 31.4 %
Rockwool 22.6 %
Picon 5.1 %
CocoPeat 4.0 %
Others (NGS) 0.5 %

Perlite offers far better control over water usage and makes what water is used more available to the plants. Many growers also find perlite far more "forgiving" than other medias---if a little too much water is used or not enough, the plants do not suffer. It also has posed far fewer disposal problems, and has potential for use in retail potting soils and landscaping after being used for greenhouse production.
In this particular greenhouse, each Perlite Grow Bag had six plants. Three would be suspended in one direction, and three in the opposite direction. Space Between Plants Working Rows Between Plants Between each row of Perlite Grow Bags, an aisle allows workers to work with the crops and harvest them.

This trend towards using perlite hydroponic systems in bags or containers is growing throughout the world. Whether driven by water restrictions or availability (as in Israel and the Mediterranean countries), or by land use limitations (as in Holland and most of Europe), or by climatic considerations (like growing in space or in Scotland year-round), or by the banning of popular field pesticides (like methyl bromide's ban in the U.S.), the use of perlite in commercial hydroponic growing is increasing, it is answering needs around the world, and it has offered a very environmentally safe and friendly way to produce more produce with less water.
Experimental Container Units (Picture at left) Research is currently underway to test long, reusable containers of perlite (hidden under the "draped" plastic covering the containers). This system would recycled unneeded water and nutrients, and reduce the amount of labor involved in changing the perlite "beds" when several crops have been grown.

April 2004 Update

I contacted Manuel to see if anything has changed since I wrote this article. He wrote back (in broken English which I have corrected a little:)

The proportion of farmers using perlite has increased and now the percentage of growers using perlite as substrate is estimated to be around 65%!

And now there is a clear tendency in hydroponics in Spain to go to perlite instead rockwool.

There are a number of obvious advantages of perite over other media. The advantages of perlite over rock wool seem to be many: duration, the maintainence of the structures, buffer capacity, volumes per unit, performance in time, etc. All these advantages are slowly creating more and more market share for perlite---not only among new farmers going to hydroponics but also among all those that have lots of experience with rockwool. Most of the growers are looking for more security, and this is provided by perlite.

As a result, the proportion of farmers using perlite has increased and now the percentage of growers using perlite as substrate is estimated to be around 65%!

1 comment:

Chauhan Dharmendra said...

Nice project of agricultural