I’ve got those in my garden; keep coming up everywhere as weeds.
Absolutely huckleberries. They grow like wildfire everywhere else in the province, but here, they do not. They are also not sold at the grocery store.
Never had one before, and I figure this’d be the only way I’d ever get a chance to.
Failing that…hey, Dragon Fruit. Cool to look it.
I bought one of these in a supermarket once and was deeply disappointed. I would compare it to eating cucumber, but without the flavour. It tasted of… well… nothing.
But maybe mine was just an atypically bad specimen; certainly this is true of the imported prickly pears (which are related to dragon fruit) we get here; they’re hard, green and flavourless, whereas whenever I have picked them fully ripe on mediterranean holidays, they have been soft, juicy and peachy-banana-melon aromatic.
I like tart fruit, so I guess I’d vote “Granny Smith” apples–but I do have raspberries growing wild in the forest outside my front door. Y’all should come here some summer if you want 'em. Innumerable raspberry bushes, all free for the picking.
In fact, I’ll go gather some now. Thanks for the reminder.
Raspberry season in southern NY State is, apparently, over. The bushes were utterly denuded of berries.
Two vegetables that I love picked fresh but are almost always disappointing in the supermarket version are sweet corn and snow peas. I’d probably go with the corn, as pea season is very short where I live. Half a acre of Silver Queen should do it.
If by the magical rules of the OP I could get more than a few months of mangoes or pineapple, I’d pick one of them.
I’m going to move from the city to a house I’m buying upstate in a month or so, and I’m going to plant these 3 pawpaw trees that have been languishing at my folks’ house for a while. I’ll let you know how delicious pawpaws are in a few years, as I’ve never eaten one.
Bing cherries. My all time favorite fruit. I’d love to get them year round. They pop up for two months each summer and again for a few weeks in January. That would save me the cost (and gulit) of buying them at $3 - $4 a pound.
Red grapefruit.
Eggplant. Can’t grow it here in the mountains.
asian pears. I can’t get enough of them.
AFAIK, you can grow raspberries here…sorta. Raspberries are a cold weather fruit, and while in the olden days we would be considered too far south, a recently developed breed has been shown to reliably grow down here (not sure which breed). Thing is, raspberry aficionados tend to turn up their noses at them, stating the fact that they can survive the heat doesn’t make up for their inferior taste. With global warming, the issue’s only gonna get worse 
Having said that, I also gotta say that blackberries (related to raspberries) make a respectable substitute and can unquestionably handle the heat. 
Oh, my… you can have the several dozen trees I killed today… They aren’t sold here because they are a notorious weed. All hedges, all fencerows have many. That said, I do love to eat them!
Me? I’d grow lemons. Lots of lemons…
Mango and pineapple. The stupidest thing I do on a regular basis is eat a tonne of pineapple when I go to Hawaii. I have it on nearly everything. Then I get home, go to the grocery store, and hey, look at those luscious pineapples (which is also my favourite pick up line). I buy one, get it home, cut it up, and “Hey! This thing has no flavour!”.
Watermelon and pumpkin. I have an expat’s lust for watermelon and pumpkin, neither of which is really available here. (Yes, they have watermelon in Holland. But they are these pathetic little tiny basketba- whoops, sorry, football-sized pale green thingies with no stripes or seeds. And they taste like water. I wants me a real watermelon.)
And also everyone I meet seems to think that pumpkins are for decoration, not eating. So every autumn i want a pumkin pie really badly and don’t get one.
Expat’s lust i tell you.
Corn. The only good corn I’ve ever had was in California. I have no idea how I got good, fresh corn there.
Come on up to the Philly/South Jersey area in July or August. The trick is to eat it as soon as possible after it gets picked – running from the field to the kitchen wouldn’t be a bad idea.
Dragonfruit, with sweet corn a close second. Gooseberries are on the list, too.
A good dragonfruit is spectacularly good. When they are so pink and plump they look like they’re going to explode. Put them on ice for half an hour and they are lovely - a combination of kiwi fruit, coconut ice and nothing at all. You can get OK version in the supermarket if you’re lucky, and I’ve had a reasonable one in Taiwan, but if I could grow them like I had them in Nha Trang (Vietnam) I’d be happy.
Here in southern California we can grow a raspberry named Bababerry. The taste is excellent and the plants don’t mind the hot, dry conditions we have during the summer.
For me, I’d love to be able to grow mangosteen fruit. I bought some fresh ones years ago from some fruit vendors in northern Burma.
I was thoroughly excited to see olives growing on my olive tree this year due to the unseasonably hot summer. Sure enough, now it’s turned just* a tiny bit too cold and wet* and the buggers aren’t ripening anymore. Much pouting, I was planning on keeping a jar of them in brine specifically for martinis.
Me, I’d grow guavas. I love being able to eat guavas skin and all like an apple whenever I’m in the caribbean, it’s my absolutely favourite fruit but the ones we get here are horrid. We’re planning an eventual move to the Virgin Islands and I’m flippin well getting my guava tree (bush?) then.