I tried from seed once. It didnt seem to like the full sun of July/August. I imagine an established tree would do just fine. Of course youll need to protect it during winter.
Its true a seedling will take awhile to mature to fruiting age and the fruit wont be identical to the tree it came from. A grafted tree should flower the first year and for sure by the second year you have one.

As with citrus and other tropical fruiting trees it is recommended to let the first year or two be for vegetative growth and sacrifice the fruit.

mike

Like Mike says, it would need winter protection. The Hass variety doesn't get so tall. I'm thinking maybe 15-18'. Some others can get up to 60' tall. Wouldn't it be WONDERFUL if there were winter hardy avocados?!

George

George- Actually upon looking online yesterday for a more mature plant to buy, not only did I find Hass, but I stumbled upon a cold hardy tree. I try to link it. It says it can withstand temps to 18 degrees. But most of the Hass variety say to 45 degrees, and from what I can tell the one winter living here, it doesn't get that cold very often.

Mike- I am actually still learning about trees of all types and had no idea you should sacrifice the fruit for the 1st few years. I will keep that in mind if I decide to get one!

Here is a link that might be useful: cold hardy avocado

Mom

Dont let the last winter or 2 fool ya. February 10 2011 the low was -12 here in tulsa. There is an avocado called Lila that it said to be hardy to 17 degrees. Personally I think the term hardy is mis understood. For one it is usually for mature plants. Sure that avocado may be able to survive a brief dip to 17 degree, like a couple hours, but i really doubt it can see that temperature for days and not be killed. that is the problem with Oklahoma. For the most part we could get away with growing Zone 8 or 9 stuff but all it takes is one week of Arctic air and those plants are toast. You could try a cold hardy avocado but for $50 bucks I would rather get a Haas or something that is well know for its flavor and just keep it small in a pot. I only use a handful of Avocado a year anyways. A 6 foot tall tree could produce a couple dozen or more easily.

mike

Couple years ago Tahlequah dropped to -16 F. I believe the high for that day was below 20 F. That's one of Oklahoma's challenges: wildly fluctuating temperatures. However, if I could grow a 6' avocado tree in a container, and get some fruit every year, I might consider it.

George

George

I grow several types of citrus here. My largest right now are a Meyer lemon and Key lime. both are about 4.5 feet tall from the container and give me a couple dozen fruit per year. Only reason I havent tried an Avocado is the cost of the tree. I havent found anywhere online that can ship one for less than 50-75 bucks. That kind of money will buy a lot avo's at the store. Im going to Houston next month and will be looking for mango and avocado but back in april when I was there I couldnt find either for less than $50. And they were small.

You do have to be diligent in root pruning and re potting but for me that is part of the fun.

here is my meyer lemon. it has about a dozen fruit set right now and is flower again.

Mike