What is the proper name for milkweed for North Carolina , Greensboro specifically
Here are pictures of the different milkweeds and the states to which they are native. http://blog.nwf.org/2015/02/twelve-native-milkweeds-for-monarchs/
Milkweed is best grown from seed as it has a taproot. It can be successfully transplanted but some loss is expected. Don't buy milkweed in small cell packs where the taproot can not develop normally. Milkweeds also spread via underground rhizomes so put it where it has room. Common milkweed, Asclepias syriaca is the one that spreads the most vigorously.