About the Blightwatch Service

The Blightwatch service is available to all users free of charge and you can register for the service by using our ‘Join Blightwatch’ section on the homepage by providing a name, email address and up to 10 postcode regions that you would like to receive alerts.

Traditionally the risk of potato blight infection has been based on the calculation of Smith Periods – a system that uses hourly temperature and relative humidity. Until now, as the Blightwatch service switches to the Hutton Criteria.

From 2017, the Blightwatch service has been using the Hutton Criteria to calculate and report Blight outbreaks across the UK. Alerts will be generated and sent to users based on the new criteria for your chosen postcodes.

By using weather forecast data for thousands of forecast points across the UK, the Blightwatch service can now provide warning indications up to 24 hours ahead of potential Hutton Criteria. It is important to understand that these warning indications are based entirely on forecast data and are subject to change, but they are a useful ‘heads up’ of the conditions that are forecast for the coming day.

As with the previous Blightwatch service, the Blightwatch alerts do not constitute a recommendation to spray but will provide an earlier warning to aid management decisions around spray timing and intervals. While every effort has been made to ensure that the information is accurate, no liability can be accepted for any error or omission in the content or for any loss, damage or other accident arising from the use of the fungicides for the control of potato blight in individual crops.