DuQuense said:You may be able to have Corn[Maize] -instead of/ with- Potatoes.
.... If there was a Subsitute already being grown, it would have been easier to change over.
Ireland, during the famine was a net exporter of food (mainly corn, beef and pork).
The reason that the potatoe was the staple diet in Ireland was that those cash crops were grown for the landlord and the tenants had to exist on other crops. The potato was the easiest as it yields the most nutients.