Ireland is fertile ground for many different crops and grazing animals.
Potatoes were not the only food stuff that the Irish ate. They had amazingly plentiful harvests. Between the years of the "famine" (EIGHTEEN FORTY-FIVE- EIGHTEEN FIFTY) there was one year of potato blight.
When another tyrannical country takes every last scrap of food away from a people, it is a genocide, not a famine.
This is what the English did to the Irish people.