Air potato (Dioscorea bulbifera) and Chinese yam/Light root (Dioscorea batatas) are relatives.
The former grows big aerial tubers/bulbils, the later is cold hardy.
Is it possible to somehow graft the air potato stem onto the Chinese yam roots and grow aerial tubers in a colder climate (7a)?
Why does your bag say "bombs"? The reason I ask is that my bag says "tiny ads" and it has stuff like this:
Justin Rhodes: How to Raise a Year's Worth of (Meat) Chickens in 58 Days