Causes of the Famine
Although potato blight itself was undoubtebly the main cause of the famine, they were many other factors that worsened the famine, or contributed to the start of it.
The famine wouldn't have been nearly as terrible if the potatoes of Ireland were genetically diverse. Most potatoes in Ireland at the time were the popular Irish Lumper variety. The Irish Lumper was susceptible to blight, and a very disproportionate share was of that variety. Because most of Ireland's potatoes were the susceptible Irish Lumper variety, when blight struck, little to nothing was left for the destitute that relied on the potato for sustenance.
The British Government was also criticized for not closing Irish ports in order to keep Irish-grown food in Ireland. This had been accomplished previously, with Irish Ports shut down and food exports halted during the famine of 1782-83 Instead, the ports remained open, and Ireland exported food even during the worst years of the famine.
The famine wouldn't have been nearly as terrible if the potatoes of Ireland were genetically diverse. Most potatoes in Ireland at the time were the popular Irish Lumper variety. The Irish Lumper was susceptible to blight, and a very disproportionate share was of that variety. Because most of Ireland's potatoes were the susceptible Irish Lumper variety, when blight struck, little to nothing was left for the destitute that relied on the potato for sustenance.
The British Government was also criticized for not closing Irish ports in order to keep Irish-grown food in Ireland. This had been accomplished previously, with Irish Ports shut down and food exports halted during the famine of 1782-83 Instead, the ports remained open, and Ireland exported food even during the worst years of the famine.