I have tried a few, bought 3 about 3 years ago. One is thriving well, the other 2 are doing ok surviving on neglect. The first year I was vigilant about giving them some protection for the winter (pine needles) but since then I neglected to do that. I really like them and have seen them do really well further inland (I am in Saco). Lori at Steeplebush Farm in Limington grows a lot of them, worth a visit to get the lowdown on their care. She is probably zone 4b.

I have had difficulty with heather in zone 5. Stock was locally grown (maybe even from Steeplebush, not sure) and winter protected - 'twas coddled. It lived, bloomed, just was never significant.

Side note - I was at Lowes a couple of weeks ago and they had a large, multi shelved cart filled with heather in full bloom - as I've never seen it before. It looked positively fake. Hothouse grown, where, I'm not sure. It kind of freaked me out, to be honest. Unsuspecting folks probably purchased...grim.

Perhaps if you were able to create a microcosm well suited to heather, it would thrive.