The Watercress Company has completed its annual biodiversity survey which promotes a better understanding of the breadth of life found at the outflows from their Hampshire farms. 

Since 2019, the grower has employed Robert Aquilina, to survey the water leaving the three watercress farms in Alresford, Manor Farm, Drayton Farm, and Bishop's Sutton, to investigate any changes and to identify any potential water quality issues.  

Overall, the findings this year were consistent with previous years. The species present were typical of a chalk stream, with good diversity and high water-quality scores. 

An impressive array of macroinvertebrates, highly sensitive to oxygen and pollution levels, were found including mayflies, stoneflies and flatworms, various variety of leech and a healthy quantity of caddisflies.   

The largest change year on year was at Bishop's Sutton where all the scores were down on 2021 but were still comparable with 2020.  Above both Drayton and Manor Farms, the results were practically the same as in 2021, although the significant increase in sand and silt above Drayton might be expected to have caused a larger decline. Below Drayton showed an increase in score compared with previous years.

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Robert Aquilina said: “This is the fourth consecutive annual survey I have taken in these three locations.  I’m pleased to say that the biodiversity remains largely consistent and shows a healthy variety of macroinvertebrates, proving the effects of the watercress farms on the water leaving the beds and flowing into the river is minimal.”

Tom Amery, MD of The Watercress Company said: “These regular surveys are an important demonstration of our dedication to sustaining the environment in and around the farms.  The effect of our farming methods on the Itchen, one of the world’s finest chalk streams, must be minimal and for this reason we keep fertiliser to a bare minimum, limit phosphate use on the farms and allow the watercress to remove as much of the free nutrients from the water as possible to assist in reducing nutrification downstream. 

“We have always listened to any challenge over the years and adapted our systems to meet the stringent permits to discharge and the requirements under Special Area of Conservation standards for the Upper Itchen River.  I’m proud that our efforts are clearly benefiting the chalk river supplies that run out from our farms evident in the range of biodiversity that lives there.”

The Watercress Company has also been holding meetings with the Hampshire and Isle of Wight Wildlife Trust to investigate the possibility of introducing water voles into the Itchen near to the outflows from the watercress farms, in further efforts to support the local environment.