Treating seeds for leafy greens in hot water prior to planting has been found to be effective in reducing leaf spot disease.

Growers at Riverford teamed up with the Organic Research Centre to test the approach in a real farm setting with environmental factors considered.

Supported by the not-for-profit Innovative Farmers network, which enables farmer-led research, the field lab at Riverford is now in its second year. The lab is investigating hot water seed treatment (HWST) as a non-chemical method of tackling the fungal disease in leafy green crops like chard.

The process involves heating seeds in water prior to planting and initial lab results had found it to be effective in killing off pathogens already present in the seed.

Crop yields were compared to an untreated control plot and seeds were also tested for three pathogens between HWST and planting. Result analysis from last year’s tests found pathogens to be almost eliminated with crop yields increased.

South West Farmer:

Result analysis from last year’s tests found pathogens to be almost eliminated with crop yields increased

Ed Scott, Riverford grower, said: “The field lab results from last year were promising and found some benefits - the hot water treatment looks to be a useful tool in helping control leaf spot and improving crop yield.

"This also helps with labour savings as it is quicker to harvest the crops if there is less disease. However, 2018 was a particularly dry year with low levels of disease in general, so we are looking forward to comparing results to further trials this year.”

Guy Singh-Watson, Riverford founder and organic farmer, said: “Farmer-led research is absolutely crucial as we are the ones on the ground and know our land better than anyone. At Riverford, we were honoured to take part in and host the latest trials into innovative crop protection and look forward to continuing in this important work.

"As more and more chemical products are withdrawn, ecological techniques like hot water seed treatment will become increasingly important. Conducting research on real farms proves the validity of the techniques in field settings and can give farmers and growers the confidence that they are viable and cost-effective solutions.”

Find out more about field labs or suggest new ideas for farmer-led research here