Spain's Greenhouse Revolution: Lessons for Modern Farming

Introduction 

If you ever get a chance to look at southern Spain from above, even just on a map, there’s a stretch near Almería that stands out straight away. It doesn’t look like farmland in the usual sense, it looks almost white, continuous, like something artificial. That’s because it is.

Across that part of Andalusia, somewhere in the region of 32,000 to 35,000 hectares are covered in greenhouses, forming what’s widely recognised as the largest concentration of greenhouse production anywhere in the world.

And it’s not just for show. From that footprint alone, the region produces between 2.5 million and 3.7 million tonnes of fruit and vegetables every year, with a turnover of over €3 billion. That’s not just a productive region, it’s a supply system feeding a large part of Europe.

It’s built around control, not conditions

What makes it interesting isn’t just the scale, it’s how it operates.

This isn’t farming that waits for the right weather window, the whole system is built around removing that uncertainty as much as possible. Inside the greenhouses, conditions are managed; light, temperature, humidity. It’s not perfect control, but it’s enough to keep crops growing consistently. And that’s really the key point: consistency.

Where most farming systems are still tied to seasons, this one isn’t in the same way. Crops can be grown year-round, and often in multiple cycles, which keeps supply moving regardless of what’s happening outside.

Most of it doesn’t stay in Spain

What’s grown there isn’t mainly for local use. Roughly 80% of production is exported, mostly into northern European markets; Germany, France, the Netherlands, the UK. And once you start looking at it that way, the scale becomes more real. For example, it’s estimated that around 25% of the UK’s imported peppers come from this one region. So what’s happening in Almería isn’t separate from the rest of Europe, it’s built directly into the supply chain.

High output from relatively limited land

Another thing that stands out is just how much is produced from a relatively small area. Up to 3.7 million tonnes of vegetables coming off roughly 35,000 hectares is a very high level of output compared to field-based systems.

That comes down to a few things working together:

• Controlled growing conditions.
• Intensive crop management.
• Efficient irrigation.
• A climate that brings strong sunlight for much of the year.

Put all that together, and you get a system that’s designed to produce continuously rather than seasonally.

There’s a lot of labour behind it

For all the talk about systems and efficiency, it’s still a very labour-heavy model. Across the wider sector, it supports more than 100,000 jobs, from growing through to packing and export.

That’s part of what makes it work, but it’s also where some of the pressure sits, particularly around working conditions and how the system is managed at scale.

It works — but it’s not without pressure

There’s no question the model is productive. But it comes with its own challenges. Water is one of them, this is one of the driest parts of Europe, so production depends heavily on carefully managed irrigation and alternative water sources.

Then there’s the plastic itself. Covering tens of thousands of hectares brings obvious questions around waste and long-term sustainability.

None of that stops the system working, but it does mean it’s under more scrutiny than it might have been in the past.

Where Ireland fits into all of this

At first glance, it feels like a completely different world to Irish farming. Different climate, different crops, different scale. But the connection is there, because it’s all feeding into the same market.

When one region can produce millions of tonnes of vegetables year-round, and ship most of it across Europe, it shapes how supply works everywhere else. For Irish growers, particularly in horticulture, that creates a very real comparison point.

You’re not just producing against local conditions, you’re competing with a system that can deliver:

• Consistent volumes.
• Predictable supply.
• High output from a relatively small footprint.

Two systems, operating side by side

In reality, there are two very different models at play here.

The system in southern Spain is built around control, scale and consistency. Irish farming, by contrast, is still largely tied to natural conditions, more seasonal, more variable, and generally operating on a smaller scale.

Neither is necessarily better, but they’re working under very different rules and when both feed into the same market, those differences start to matter.

Conclusion

The “sea of plastic” in Almería is often talked about because of how it looks. But what it represents is probably more important. It’s a version of agriculture that’s less dependent on weather, more focused on output, and tightly connected to supply chains.

That doesn’t mean it’s the direction everywhere goes but it does set a benchmark, whether intentionally or not. Because once that level of consistency and volume exists in the system, it becomes part of what buyers expect.

And that’s when it starts to influence everyone else.

*By Anne Hayden MSc., Founder, The Informed Farmer Consultancy.