Sonja,
You would think that potatoes and sweet potatoes are closely related plants, but they are actually have quite different needs, characteristics and growth habits.
Firstly, sweet potatoes grow a vine as opposed to a bush. Secondly, sweet potatoes just love high heat where potatoes are a cool weather crop. Potatoes require fairly high soil nutrients, but sweet potatoes can grow on very poor, sandy soil. A potato plant typically produces 3-5 fist sized spuds where a sweet potato can grow a tuber larger than a football—I have grown them that large before, but when they get that big, you might consider eating paper before eating that potato as it gets really starchy. Finally (I could go on but I will stop here), while both have their pests, I think everything likes to eat sweet potato vines. I have planted sweet potatoes several times, but typically the
deer get them first.
Sonja, if you want to plant sweet potatoes, they might be the perfect
permaculture plant—just protect them from pests.
Eric