What's the best area to live in Hawaii for growing, folks? Thats where we would LOVE to be this winter. Hoping for next winter though, for sure. We have a friend who's gone there a few times and it sounds bloody great.
The south and west sides of any of the islands are sunny and dry almost everyday of the year, but they are also the most crowded and most expensive sides too. If you're just growing small-ish plants for mostly personal consumption than anywhere should be fine if you can find a suitable house for growing. If you're thinking commercial then on Maui most of the commercial growers live Upcountry. Specifically Haiku and Kula. Greenhouses are a good idea most anywhere Upcountry and further out South or East like Hana or Kaupo (the wet side of Kaupo). Actually parts of Kanaio and Kaupo (the dry side of Kaupo) would be really great spots to grow, but you have to haul water out there. There's almost no county water out there and it doesn't ever rain enough to fill up catchment tanks and it's all pretty far out there, but it is some of my favorite area on this island.
Like waterproof said, the east side of the Big Island is the only affordable place to live besides some parts of Molokai, but it rains like crazy. Mountain View, where I used to live gets an average of 160" of rain per year. It's the wettest inhabited place in the US so yeah, greenhouses are a good idea.
And I mentioned Molokai, but you don't want to move there unless you know how to befriend locals like it's your job, ha ha! They even say, "Don't come unless you're invited" and that's for real.
If money doesn't matter then I'd look at the south or west sides of Kauai, Big Island or Maui. The north shore of Maui is nice and there's pretty decent growing weather if you don't get out too far east and Hawi on the Big Island is really nice too.
I left out Oahu just because I don't know the island very well and there's a lot of people there and it's not my thing, but a lot of people like it there apparently.