Potato Blight is very dangerous; it can wipe out a full crop overnight. In a sack or a crate, it will travel from potato to potato, ruining them all. Potato Blight is one of the worst diseases you can get while growing potatoes, and the moist, humid Irish summer climate is perfect for spreading it.
Causes of Potato Blight:
Potato Blight is caused by a fungus called Phytophthora infestans, which can spread to other member of the potato family, including tomatoes. It spreads through the air and develops when the weather conditions are warm and humid, particularly during a Smith Period. A Smith Period is a 48 hour period in which the minimum temperature is 10°C or more and the relative humidity exceeds 90% for at least 11 hours during the first 24 hours and at least 11 hours again during the final 24 hours. However, any period of warm, humid weather increases blight risk.
Symptoms of Potato Blight:
The potatoes will eventually turn into soggy, foul-smelling masses.
Treatment of Potato Blight:
Prevention of Potato Blight:
The best way to prevent Potato Blight is to plant a good Blight-resistant variety. The best product on the market for the prevention and control of Blight, is Proxanil.
Blight Resistant Varieties:
The recent development of Sarpo Hungarian varieties is a real breakthrough in potato cropping. They are extremely blight resistant and are available from Horkans. Sarpo Mira is a wonderful variety; it is floury, well flavoured and a terrific cropper. It is a nice red skinned potato with lovely white flesh. There are other varieties of potato with varying degrees of blight resistance listed below:
Please remember to follow instructions carefully when using chemicals.