If you’ve ever tried to grow your own potatoes, you’ll probably be all too familiar with potato blight. But are we gardeners to blame for poor potato crops due to the spread of blight from our gardens?
Late blight (Phytophthera infestans) is a devastating fungal disease of potatoes. It was one of the main causes of the Irish potato famine in the 1840s and can still ruin crops for gardeners and growers today.
The potato industry has been hit by a ‘perfect storm’ of misery this year after the wettest summer in 100 years and the dullest since 1987; both of which have badly hit yields and quality. The worst crop in 35 years means the wholesale price of potatoes is almost 80% higher than last year with further increases expected.
Amateurs to blame for spread of potato blight?
Alan Stephenson, chairman of the Potato Council, has pointed to amateur gardeners for a ‘disproportionate amount of overall blight pressure’, suggesting that inexperienced gardeners could make the problem worse by composting infected potatoes, and allowing wind-borne spores to spread. He told The Grocer that:
‘People should be encouraged to grow their own vegetables to learn about the origins of their food. But the blight risk is real and it would be preferable if people bought healthy, well produced potatoes from their retailer rather than grow their own.’
But is it fair for farmers to blame gardeners for their poor crops? There have been double the number of Smith periods (when conditions are ideal for the spread of blight) this growing season, so it follows that blight will be more prevalent, whatever gardeners are doing.
And I’m sure most gardeners are wise enough to know that they should take measures to stop the spread of blight in their garden or plot by removing and destroying infected plants as soon as they’re spotted.
Blight resistant potatoes
Some potatoes have been bred to be blight-resistant, and a trial by Which? Gardening in 2009 showed that two varieties, Sárpo Axona and Sárpo Mira, first bred in Hungary by the Sárvári family, showed good resistance to blight.
Dr David Shaw of the Sárvári Research Institute in Wales (which breeds blight resistant varieties) was quick to respond to the comments asking:
‘Why do gardeners bother to grow their own? Exactly because they do not want to buy “well-produced potatoes” sprayed every week with chemical fungicides’.
Sadly, the Institute is faced with closure – ironic given that coming up with new, blight-resistant varieties has never been more important.
I have to admit that after suffering from infection myself over the past few years, I have now made the switch to resistant varieties.
Have you been hit by blight this year? Do you think gardeners are to blame for farmers’ poor crops – or is it just a case of a poor year?