/ 1 March 2023

Bottoms up! Gin crafted from invasive water hyacinth plaguing Bronkhorstspruit Dam

Whatsapp Image 2023 03 01 At 7.02.13 Pm
Peach started out by making normal gin and infusing it with the water hyacinth and a little bit of cucumber. Photo: Supplied

A craft distillery in Bronkhorstspruit has created a novel use for the damaging water hyacinth that is plaguing the Bronkhorstspruit Dam — turning the invasive superweed into gin.

The hand-crafted Green Monster gin is infused with water hyacinth, while the Purple Devil is distilled using the aquatic floating weed and has a purple tinge, like the hyacinth flower. Bottles of it carry the slogan, Drink our dam clean.

The products are the brainchild of Bronkhorstspruit resident Phillip Peach, who lives on the edge of the dam, and started making the gin at his small home distillery to raise awareness about the infestation of water hyacinth

The fast-growing plant is described as the world’s worst aquatic weed because of its invasive potential, its destructive effect on aquatic biodiversity, and the heavy costs of trying to control it.

“The Bronkhorstspruit Dam has always been quite clean,” Peach explained. “We didn’t have a hyacinth problem like Harties [Hartbeespoort Dam] and other places around South Africa, but a year or two back the hyacinth started creeping up on us. It’s giving everybody a bit of a fright and everybody is trying their best to sort the problem out.” 

How the idea was planted

Peach, who works in the construction industry, told how he and Paddy Waller, a director of the Bronkhorstspruit Catchment Management Forum, were sitting at his home one night when the idea took root. 

“I told him [Waller] that maybe we must just do a bit more awareness because a lot of people who don’t have a view on the dam or who haven’t got boats going on the dam, and even if they live by the dam and they’re close by, they don’t realise the problem that this water hyacinth is.

“And I thought, well, let’s try and use the hyacinth to make gin and to try to create awareness and whatever sells, I will give a certain amount to the forum or to anybody that helps fight the problem that we’ve got.”


Peach started out by making normal gin and infusing it with the water hyacinth and a little bit of cucumber. “It turns green and we call it the Green Monster. That came off quite nicely. The colour is green, which I was worried about in the beginning, that the people are going to feel a bit offended because it feels like the dam, but it also brings them closer to the problem because they can see it. But it doesn’t taste dammy, you know. It actually tastes damn good,” he laughed. “This gin,” he said, has “quite a mellow taste”.

For the Purple Devil, he fermented the water hyacinth from the start. “The problem we’ve got is that the hyacinth plant doesn’t have a lot of sugars in it so I had to add sugar or seasonal fruit that is in the area at this particular time, just to bump up the sugar and to get the fermentation going. And that, when it runs through, it comes out a clear gin. 

“Then I colour it purple like the hyacinth flower and we call that the Purple Devil. I must say, the ladies are quite attracted to the purple one. Everybody is used to the pink gins — this is now a purple gin and it relates not just to the hyacinth but to the flower as well.” 

The response has been overwhelming, Peach said. 

“The people around the dam and everybody, they started buying into this and the awareness is really working … If you start speaking to people in places where there’s dams, everybody’s got the hyacinth problem … and if we can drink the dam clean you know, we’ll try to do that as well.”

Raising awareness

Waller, too, praised the gin. “The purpose obviously was to create awareness of our problem and what a fantastic way to do it,” he said.

The water hyacinth coverage of the dam itself is now about 8% to 9%, “which by some standards is low but unfortunately, it’s spreading rapidly,” he said. 

“So, if our control efforts don’t work and if we’re unable to get sufficient funding to really ramp up the control efforts, then who knows? In the next 12 months, it could be completely covered and at the rate it’s going now, we’re definitely going to be a version two of Hartbeespoort Dam, without a doubt.”

The hyacinth invasion is the consequence of sewage loads entering the dam upstream from Delmas. “We’ve been fighting the Victor Khanye municipality for five years now and it’s been problematic, in fact, for over a decade there.”

Rearing hyacinth-eating bugs

Bronkhorstspruit Dam, Waller said, is a huge tourist destination. “Every weekend, there’s boating and fishing, and we’ve got a few day-visitor resorts and those are always packed on the weekends. There’s several residential estates around the dam, there’s a nature reserve, there’s a catamaran club and there’s an economy that thrives around the dam, so it’s going to be tragic if we end up like Hartbeespoort Dam.”

The forum is working with the Centre for Biological Control at Rhodes University to rear and release water hyacinth hoppers onto the dam. These biological control agents are host-specific natural enemies of the water hyacinth, that are sourced from the country of origin of the weed, that can only complete their life-cycle, and feed on their target weed.

“We are rearing five stations and are in the process of trying to get another three and hopefully it works … The minute we saw hyacinth in the dam we tried to start mobilising with what little funding we had and creating awareness and building up the networks to try and fight it, we’re hoping that we’ve got an early start … It’s not regarded as the world’s worst invasive aquatic plant for nothing, it’s a tough plant to defeat, it really is.”

Integrated plan

Cara Stokes, the chairperson of the forum, said the gin is “bringing awareness that is desperately needed about the state of the water in Gauteng and surrounding areas. 

“It’s an incredibly unique way of using hyacinth. Look, you can’t use tons of it, but just to bring awareness is incredibly good. I’ve heard the gin tastes very good and there are lots of good reports about it. We’ve received our first donation from the proceeds, which is amazing. They obviously sold quite a lot already. 

“However, we still don’t have concrete solutions to even fix the problem and we need everybody to assist and everyone to come to the party with cleaning the water upstream otherwise we’ll have enough gin to become multi-millionaires,” she said. 

The forum has an integrated hyacinth control plan in place to tackle the hyacinth, which includes mechanical control, chemical control as well as biological control. “The mechanical control is that we’ve been removing hyacinth manually for the last six months, we’re waiting for our authorisation to do sub-lethal spraying as they have done at Roodeplaat Dam in the past as well as releasing a large number of bugs. We have to release 400 000 bugs, I think, and we’re at 94 000.”

Incomes are being affected. “The nature reserve has reported significant loss of income because of the hyacinth and then on the properties as well, the fishermen don’t tend to like hyacinth because it affects their ability to fish, which is obvious. And we also need to work upstream, we also have a wetland task team to identify and design a number of wetlands … to mitigate and clean the water before it even gets to the dam.”