You can plant them now. I live around the Plant City area, don’t have alot of experience with pawpaws yet, but they seem to remain dormant till April-ish even if it warms up. At least my last one did. I bought and planted 3 in October (got them at the USF plant sale). They used to have a fruiting triloba at the USF botantical gardens in the 90s, so its possible for them to fruit here. Its keeping them alive for the first couple of years thats the hard part.