Wilma is said to be hardy to the mid teens without damage. I believe there are others as well.

One problem that I can see, in order to obtain a reasonable crop, doesn't one require a type A and a type B avocado? -Millet (412-)

That is what I thoight. There are a few different varieties from TX, I'm not sure of the A/B types that they are...

Their are some that do not require a type A and B. Someone here has to know.

j3u5a8n, that is the first I have heard of that. As far as I know with avocados one type is active in the AM and the other type in the PM. - Millet (412-)

Here in southern California, Hass avocado country, you don't need an A and a B (although it will increase production). That's because the air is cool during bloom time here and the flower times overlap. In more tropical areas (such as Mexico, I don't know about Florida or other places in the South) a B tree is necessary. My neighbor's tree goes off with 100- 200 Haas "A" every year and no "B" tree around. Your production may be different.

Try the Mexican varieties such as Mexicola and Bacon for resistance to cold. Mexicola in particular has a very nice anise flavor to it in my opinion and I would recommend it. Bacon is watery.

Laaz isn't there a a large, single fruiting avocado tree in downtown Charleston? I know it exists but couldn't find it's exact location when I looked for it. I did indirectly get a rooted cutting from that tree years ago from Ned and it is doing great. It remains as potted plant so far for me but should do fine in your location. I remember an older discussion about it and it was thought to be a Gainesville or Gainesville seedling.

The observation about Hass holds true for some (not all) of the cold-hardy types. Gainesville (type A) fruits very well on its own if the nights are chilly during the bloom. The low night temperature keeps the afternoon flowers from closing before the morning flowers open, so some self-pollination occurs. Brogdon (type B), on the other hand, seems to be self-fruitful regardless of night temps. And Duke (I believe type A if I remember right??) never is self-fruitful no matter how cold it gets during the bloom. We have to huge trees of it that average no more than a dozen fruit each, per year, due to their isolation (several hundred yards) from the next nearest pollenizer.

http://www.postandcourier.com/news/2008/sep/21/avocado_tree_amazes_fruit55183/

No information on it's location. I would like to try a Opal Holland and Wilma in the spring if I can find a source. Maybe get a but stick from G as well.

Yup, that's the one I have in the article. No prob on a scion later.

You may want to look out for Brazos Belle, Lila, Pancho, Arizona, Winter Mexican and Joey as they are reportedly very hardy varieties as well. Rivers End Nursery and Plant o Gram had a few of those in stock previously but I'm not sure what they have available now.

I tried to propagate several "cold hardy" avocados a couple years ago with little to no success. Citrus budding is a slam dunk for me and I've budded hundreds of them but on avocado none worked.

I've heard avocados are easy to propagate. I never figured it out. My trees came from Just Fruits in Florida one of which was "Gainesville.

I don't think avocados are possible in the SE Texas area without a LOT of protection. It wasn't worth it for me and I gave up.

I'm aware of the guy in San Antonio with his Opal and Holland cold hardy selections. Hmm, San Antonio is south of me.

Mr. Texas, I've managed to T-bud a few over the years, but it is not easy. The bark is just too thick and tends to splinter. However, chip buds are fairly easy. But the very easiest method, and by which maybe 95% of all Florida trees are made, is to cleft graft a leafless scion, 2-3" long, on a young seedling, when the seedling's first leaves have just reached full size and the trunk is still pink and soft like celery. The only big challenge there is getting seeds that are big enough to make a thick enough stem right away, to handle the thickness of your scions. We do this mid-November through December, and even beginning grafters commonly get close to 100% success. It's also reasonably easy to cleft graft onto somewhat older seedlings.
Malcolm

I've tried Mexicola Grande and Joey. I planted them this spring and the drought got them, so I can't testify to their cold hardiness. We had 100 degree temps and no rain for months. I had them on the drip irrigation system, but they really hated all the salts in the city water. So... they don't do well if they can't have any nice clean rain.

Lila is supposed to be hardy into the teens. I've seen them at local nurseries. I would have picked one up had I not bought they other ones on impulse. I didn't do my research until after I got home. Bummer.

If you want Opal or Wilma I think you have to go to Devine, TX to get them.