I am not completely sure, there may be different answers to this question:
Canadian Shield is not suitable for farmland, because it is very rocky.
Great Plains haven't been suitable in the past, because the land is very dry.
Greenland is covered in ice, although there are many places where farming is very successful.
Yucatan Peninsula is more or less a swamp today, but farming is possible.
Wind belts relationship between continents and oceans
topography
It established a way to transport textiles and agriculture trade from Africa to Europe, during the early-mid 1800s it was a big accomplishment.
