In Mexico, they call avocados ‘green gold’,
because they’re worth nearly $3bn in exports every year.
But every day, those avocados suck up 9.5 billion litres of water.
I’m travelling to two different growing areas to see how that thirst affects growing
techniques, and the impact technology can have where water is scarce.
My first stop is with Manuel Macias, an agronomist at a farm in Michoacán state, in western
Mexico.
Here the fertile land and abundant water sources make it easy to grow avocados without using
irrigation technology.
From a 13 or 14-year-old tree, you can get 200 or 300 kilos of avocados in a single harvest.
Mexico produces close to half the world’s avocados, the vast majority in Michoacán.
But with worldwide demand estimated to be growing at around six per cent a year, other
states here are trying to cash in, not that it’s easy.
They have to invest a lot more to equal our production, to make it profitable.
It’s much more expensive to produce.
My next stop is with a farmer who can’t rely on nature to manage a more limited, and
precious, water supply.
We need to make sure we travel there by daylight.
That’s because in some places, this lucrative industry has been targeted by organised crime,
and it’s too dangerous at night.
We’ve just seen how avocados are grown traditionally in Michoacán.
Now I’m on the way to the neighbouring state of Jalisco to see how a farm uses irrigation
technology.
In Jalisco state, water is in high demand.
About 80 per cent or more of the available water supply is used every year.
Antonio Martín’s farm is on a hill, and at the top a pump draws water up from a deep
well to fill this large reservoir.
The water from this reservoir passes through a computer which administers organic nutrients
and distributes them along irrigation hoses.
Drip irrigation was developed in Israel in the 1960s.
It can significantly reduce water consumption, help combat soil degradation and boost yields.
Antonio has had this irrigation system for five years.
The difference between having an irrigation system and not having one is colossal.
You can double production or more.
Avocados are actually far from being the thirstiest food to produce.
Rice, chicken, beef and chocolate use much more water.
But in the last two decades water consumption for avocado production has doubled in Mexico,
so anything that can slow that thirst is worthwhile.
85 per cent of orchards in Jalisco now use drip irrigation or micro-sprinklers.
Oscar González’s company provides the irrigation system on Antonio’s farm.
Here we actually have the brain of the system.
It’s actually a very sophisticated irrigation controller.
It actually knows when to irrigate, how to irrigate, for how much time, what kind of
fertiliser you want to inject into the system.
The system is linked to Antonio’s computer, where he can make adjustments, but he’s
already looking to increase its sophistication.
The next step, is to install a system in which we can monitor the humidity of the soil remotely
by telephone and be able to control the humidity of the different areas of the farm, giving
each tree the water it needs precisely when it needs it.
At the moment only about one and a half per cent of farmland globally uses precision irrigation.
But the global drip irrigation market alone is projected to grow from $5.5bn in 2020,
to more than $9bn in 2025, according to Markets and Markets.
High capital costs mean its use currently tends to be limited to cash crops, like avocados.
But as the planet’s temperature rises, along with the demand for food, the use of irrigation
systems, either as complex as Antonio’s, or simpler, will almost certainly have to
rise too.