I bought my pitomba as a 3gal from Pine Island 4 years ago.  Its just under 6' now.  I get a little dieback each year, but so far I get more growth.  It flowered for the first time 2 years ago but this is the first year it has set fruit. 

I have 7 planted 8' apart that I want to grow into an informal hedge and I get lots of fruit from each (well, about 30-50 from each tree, but they are still in the 4-5' range).  My daughter loves the flower petals so each year we go from tree to tree pulling off the petals.  I am betting this helps in pollinating.  Maybe you can try something similar?

I am in zone 9a zip 33541 and it does beautifully here.  Here is a pic of mine from 2010

Tomas,

Are these the Pakistan and Shatoot mulberries?  I can tell you from experience with the Pakistan that cuttings can not only push buds but even try to fruit without any roots.  I have never been sucessful with rooting Pakistan, though I have tried many times.

I think it will be hard to tell without fruit.  I'll have to look closely at my emerald/jewels tomorrow to see if there is a noticably difference in the leaf.

Adam, have you ever tried the Surinam from Palma Sola?  I don't remember what its called now, something with 'Jim' in it I think.  Anyway, I think that tree produces black fruit that tastes like a sweet bell pepper.  My wife likes that one alot.  I planted some seeds a couple years ago from that tree and have one fruiting, but it looks like it will be red so we'll see about taste.

Wow Jsvand5, thats strange.  I have never had worms in my mulberries and have a huge Pakistan, plus I don't think I live too far from you..  I also recently added a Silk Hope and Shangrila. 

I have no doubt that mango could be breed for cold tolerance.  I work in Tampa and there are hundreds of mango trees in this borderline climate.  Most are in areas near the water, like South Tampa and Palmetto Beach.  However, the two bad winters we had a couple years ago really proved the point to me.  In Palmetto Beach there is a mango tree in nearly every yard.  It got very cold and there were mango tree's 50+' tall that died out while some of the same height had no damage.  Same effect for smaller trees. 

Now most of the tree's are grown from seed.  The avocado has been a great sucess story for finding good tasting varieties that can resist cold damage.  Mango can be the same, but it needs to be realistic how cold they would be able to endure.

As far as named cultivars that can presently handle the cold, no clue.  They are almost all bred for taste, dwarfing and disease resistance.

Probably too late Pug, but you can try Crowleys off Fruitville Rd.

I'll respond though I am a few hours north of you.  I have 6 feijoas that produce quite well here (all seedling, no named cultivars).  I believe it is generally accepted that cross pollination is necessary.

Adam

Have you tried Psidium friedrichsthalianum?  By far my favorite guava for fresh eating but it grows so very slowly.  I have not tasted P. nana though.

I've had a meyer lemon for years and I love them.  The tree is more compact than say a grapefruit and produces quite heavily.  The fruit are sweeter than other varieties since it is really a hybrid, but still not sweet enough for fresh eating.  Though I think your south enough it wouldnt effect your tree's, they are quite cold hardy.  Mine experienced 18f for several hours with very minimal damage.

In Tampa I can get Florida lychees in a 50lb box for $50.  Otherwise I have to pay like $8 for a small clamshell.