I don't know whether or not you would have a vine similar to Blackie, since all sweet potatoes/impomea batata are notorious for genome variation when produced from seed (that means the babies quite often bear little to no resemblance to the parents). That's why sweet potatoes usually grown from slips or a piece of a tuber from the originating plant. If you have time, it might be fun to see just what sort of plant the seeds would produce, but don't expect to get Blackie juniors.

if you want clones- save the tubers, I dig up the smaller ones every fall, and keep them in dry sand with my dahlias.

but the seeds are always an interesting experiment in genetics- you literally never know what they will produce- but then mine don't get as far as seeds very often- I was kind of surprised to find mine blooming with the morning glories this morning !

Thanks for the response. I will dig up the tubers--it is still very warm during the day. It drops to the 70s at night. I was just curious because I never seen one bloom let alone think that they would produce seeds. I will try the seeds just to see what I get. It is blooming just like a morning glory--the floweres are very pretty --pink against the black leaves. thanks again.

I found lots and huge tubers and I was wondering if they are eatable?