An evolving sector
Vialux was created because growers needed a solution that didn’t yet exist.
Back in the 1980s, the horticulture industry was undergoing a fundamental shift—from growing in soil to growing on rockwool substrate. That change picked up speed when methyl bromide, the standard for soil disinfection for years, was banned in the Netherlands in 1982 and then phased out worldwide. Rockwool seemed like the answer: no soil, no need to disinfect it.
But the switch brought a new problem of its own. Once pathogens got into the drain water, they could infect the whole crop via the irrigation system. The industry needed a new solution.
So, Priva came up with one: UV disinfection. Measurable, reliable, and easy to control. No chemicals, no residues—just water that’s safe for plants, and people.
“We went with UV because you can measure it, control it, and rely on it,” says André de Raadt, Portfolio Manager at Priva. “We do what we promise and always go the extra mile.”
35 years is no coincidence
The very first Vialux HDUV system was sold by Jan Vos to a grower in the south of the Netherlands. Some of those early systems are still running today.
“It was a good system, and I sold a lot of them in the province of South Holland. The first version did use quite a lot of energy, though, so we developed the Vialux M-Line to fix that. But right from day one, we knew the system worked.”
Jan is always happy to tell the story. However, it relied on four separate UV lamps—a system that simply wasn’t scalable for commercial growers. So, Priva took matters into its own hands.
“We wanted one chamber, one UV lamp, and one UV sensor. Simple and reliable. Once the water has been through the chamber, it will have been disinfected. The competitors used multiple chambers and an LDUV setpoint, but we wanted to do things differently – easier to maintain, easier to scale up.”
Flexibility was key right from the start. If you’re growing multiple crops, it’s easy to switch between tanks. And you can adjust the water flow, so if you need extra protection from challenging diseases like crazy roots (Rhizobium rhizogenes), you simply slow down the flow, so the water is exposed to the UV for longer.
“One of the big advantages of UV is that it doesn’t strip nutrients from the water. You disinfect, but you don’t lose anything. That’s what makes it profitable.” — Jan Vos, Vialux’s first salesperson.
That’s what real trust looks like – growers who made a choice 35 years ago and have never looked back.
Today, Vialux M-Line systems can be found in greenhouses worldwide, from the Netherlands to Dubai to the U.S. The core concept hasn’t changed at all: a system that does exactly what it promises, year after year, greenhouse after greenhouse.
What 35 years in the field have taught us
André de Raadt has been keeping a watchful eye on developments in horticulture for years. He sees a sector that’s moving fast – facing challenges far beyond just technology.
New substrates, new challenges
Switching from rockwool to organic substrates like coconut fiber may seem minor, but it has significant implications for water disinfection. Rockwool offers very consistent conditions and requires precise control. Coco is more forgiving when it comes to mistakes, but its composition is less predictable, which means a one-size-fits-all disinfection system doesn’t always do the job.
“Horticulture is constantly evolving,” says André. “New substrates, new genetics, new growing methods. At Priva, we’re always thinking about how we need to respond.”
Knowledge – the real challenge
Knowledge makes all the difference. “It’s all getting more complex,” André says. “New substrates, new growing methods, new regulations. So, growers tend to fall back on what they know and understand, even when there are better solutions available.”
A grower who understands what their water is costing them makes better decisions. The Vialux calculator lets you work out exactly what you’ll save on water, fertilizer, and costs, tailored to your setup.
Combined systems are the future
Priva is already working on the next step: combined systems that adapt to exactly what your crop needs.
“We’re seeing that one system often just isn’t enough anymore. With coconut fiber and other organic substrates, sometimes you need both UV and ultrafiltration to really keep your water clean. We’re working on ways to make those combinations simpler and more affordable for growers.”
Real-world results
At Hollandia Greenhouses in North America, water disinfection has become part of their business model.
They recirculate up to 80% of their irrigation water. “We’re not allowed to discharge anything, so reusing it is our only option,” says Operations Manager Terry Pastorek. “But to be honest, it’s just the smartest economic choice.”
With Priva Vialux at the heart of their water treatment strategy, Hollandia saves $4,000 to $5,000 per week on fertilizers alone. The nutrients that would otherwise be lost are fed back into the crop. In most cases, a Vialux system pays for itself in under three years.
Read the full story here.
What’s coming next
UV-LED technology is on the horizon. We are already in discussions with suppliers, but the efficiency isn’t quite there yet for commercial use. “We think it’ll be at least another five years. But we’re tracking developments closely, and as soon as it’s ready, so are we.”
Regulations are always a factor. Current UV lamps contain compounds that regulators view as chemical waste. Priva is keeping a close eye on developments and is ready to move to UV-LED as soon as it delivers the efficiency growers need.
Meanwhile, our systems are only getting smarter. The latest Vialux M-Line HT automatically adjusts UV-C dosing based on measured water quality, integrates fully with Priva Connext and Compact CC, and handles high water volumes with smaller, more energy-efficient reactors.
“We always go for the best solution, not just the easiest,” says André. “Horticulture is constantly evolving, and we are evolving right alongside it.”
35 years on: the key question is still the same
“What stands out to me most is just how much we’ve learned from growers and partners. Every conversation, every installation has made us better. That’s the foundation we continue to build on.”
Thirty-five years ago, horticulture was faced with a real challenge— today, our solution is at work in greenhouses around the globe. The only question is: are you using it yet?
