The challenges of 2017: Potato blight.

Late potato blight (Phytophthora infestans) proved to be a major issue for us last season – resulting in significant yield loss.

Late blight is one of the biggest challenges facing potato growers in general, for organic growers it’s a massive problem.

Blight pressure during the 2017 season was particularly high; in addition, almost all the UK outbreaks of the strain EU37 were in the West Midlands. This strain of blight is particularly virulent and out-competes all of the other strains.

As an organic grower the only way of controlling potato blight is to use a product called Cuprokylt. During the 2017 season an emergency authorization was granted. However, this emergency authorization can only be made twice, so 2018 will be the last authorization year.

It is therefore extremely unlikely that we will be allowed to use Cuprokylt after this season. If this is the case then the sustainability of UK organic potato production will genuinely be at risk.

Going forward we would have to rely purely on varietal disease resistance, and cultural control methods – e.g. early season production, short season crops, and early burn down. Unfortunately this would greatly reduce the number of varieties that we currently grow.