A Natural Way to Fight Water Pollution—With Flowers

Algal blooms are becoming a bigger problem each summer in our lakes and rivers. One unexpected but effective way to help tackle the issue starts right in the home—with how we manage our wastewater.

At Herr Ltd, we’ve developed a simple, nature-based solution that works well in small homes: using diluted urine to grow flowers indoors. When rainwater is mixed with separated urine and used to water indoor plants, it creates a natural fertiliser. This helps reduce the nutrients that would otherwise leak into groundwater and contribute to pollution.

Why Urine Matters

Most people don’t realise it, but our urine carries around 70% of the nitrogen and pharmaceuticals in household wastewater, and about half the phosphorus. These nutrients, when they make their way into lakes and rivers—especially during summer—can trigger algal blooms that harm wildlife and spoil natural beauty spots.

In homes with only one or two people, reusing this nutrient-rich liquid to grow flowers indoors is a smart and attractive option. Not only do you get vibrant, blooming plants inside your home, but you’re also helping the environment by reducing pollution at the source.

A Better Alternative to Septic Tanks Alone

Septic tanks and the percolation systems that follow them do a poor job of dealing with nutrients and pharmaceuticals. Once wastewater goes underground, it’s hard to capture or clean up. Garden plants can’t absorb what’s already gone deep into the soil.

But by using the Herr indoor flower growing system, those nutrients are held in place long enough for the plants to soak them up. It’s a simple, beautiful way to close the loop.

And if you combine this with a toilet composting system, you can remove another 15–30% of pollutants from your home wastewater. That’s a big win for any eco-conscious homeowner.

A Working Example in Dublin

You can see this system in action at the Rediscovery Centre in Ballymun, Dublin, where both the urine-fed flower beds and composting toilets are being used successfully. These systems can be built into any new eco-home and are a smart addition alongside a standard septic tank—which is still useful for dealing with kitchen fats and greases.

With climate change increasing the frequency and severity of algal blooms, it’s time for a rethink. If you’re building a new home or upgrading an old one, why not take a greener approach?

Let’s Talk

If you’re interested in learning more about how to add the Herr flower growing and composting toilet systems to your home, visit www.herr.ie or call us at 00353 86 1700569. We’d be happy to help.