1) What would be needed?
2) what are the demographic consequences?
3) What impact on British Colonization the South East of North America?
I dunno; this is a fairly early POD, and difficult to pull off; at least with marijuana IOTL, a significant part of the reason it became so taboo, especially when it came to the South(and parts of Western society, too; remember, opium was the subject of a similar panic in California earlier on.), is because it was indeed associated with "those people", i.e. minorities, like the Latinos(Mexicans, mostly) and blacks.....(of course, the *whole* situation was a bit more complex than just that one thing, but no doubt that prejudice did play a notable role in "Reefer Madness", etc.).
But without race as a fully developed concept, it becomes that much more challenging to convince people not to engage in tobacco consumption. Dragos did, however, mention the "A Counterblast to Tobacco", and it possibly gaining more traction.....the question is, how?
Alternatively, try to have the Puritans spread out a little further than they did IOTL.....maybe they make it to OTL Delaware or *northern Virginia, even?