"New" super cold hardy avocado, variety 'Austin Star'

[Mark in Texas]

Lady from a Texas gardening group messaged me after purchasing one of these expensive avocado trees called 'Austin Star'.   My feeling is it's a knockoff of one of the pure Mexican avocados I call the "Tex-Mex" trees - Joey, Wilma, Fantastic, etc.  Kicker is this tree apparently went thru 10F during our Feb. Uri ice storm.  What the quality of the fruit is remains to be seen.  Even the Mexican criollo's found in the Mexican state of Nuevo Leon, highlands around Monterrey and Saltillo, never get down that low.

The story of the source follows:

https://lonestarnursery.com/products/avocado-austin-star?variant=39351648550975

Hi Debra, and thanks for your recent order! You’re one of the lucky few that was able to snag one of these trees. Here’s what we know:

It sustained temps under 10 degrees.  It was covered and heated.  The power went out day one and the cover only allowed it to be a few degrees above the temps around it.  Our estimations is that was below 12° at a minimum.  It is definitely cold hardy, and until the last unprecedented freeze had thrived.  In 2020 it produced hundreds of avocados only being in the ground for 7 years.

Please let me know if you have any other questions

Sincerely

Flint
LSN🌟🌱

[lebmung]

The tree was undercover and heated probably with a heating cable that means it had a microclimate, then it should survive. To be truly cold hardy should be expose directly to that temperature.

[Mark in Texas]

The tree was undercover and heated probably with a heating cable that means it had a microclimate, then it should survive. To be truly cold hardy should be expose directly to that temperature.

Spent 45 minutes on the phone with the vendor that has been working with this 40 year old tree in S. Austin.  It took days of below 12F temps (11C) and below.  There was some die back.    Really an incredible story including his technique of getting 50% rooting takes  of cuttings.  Parent tree is 35' tall with a 4' girth trunk.  Says the fruit is very rich.   

It's gets more crazy.   Tree does well on its own roots in the limestone based soils too.   Said it fruits very heavy, a typical black Mexican race fruit with thin skin.  Anise smell to the crushed leaves. 

Will get some wood eventually.

[kingoceanos]

Just on the off chance you get to much, I'd be happy to buy some from you. ( but not at that crazy high price she paid.)

[kingoceanos]

Sorry forgot to ask can you give us the details on his rooting technique? It might be worthwhile to give it a shot at least if the root-stock survives it would come back true from a freeze.
Thanks Mark

[brcb7tuner]

I had about 6 of the common text mex avocado make it through 13 degrees here in Louisiana with a couple inches of die back. They only had 2mil plastic wrapped around them with a open top 5-6ft tall.

[850FL]

Sorry forgot to ask can you give us the details on his rooting technique? It might be worthwhile to give it a shot at least if the root-stock survives it would come back true from a freeze.
Thanks Mark

Yeah what’s his method?

Also what about fungus resistance?

[sc4001992]

Rooting avocado is not that easy. Looks like I finally have one avocado cutting that is growing leaves but I will need to wait another month to know for sure if its got roots. I don't want to disturb it now since it's the only cutting that I planted that has not dried up/died this year. I must have tried rooting over 80 cuttings this year and so far only 1 looks good still.

[Mark in Texas]

Sorry forgot to ask can you give us the details on his rooting technique? It might be worthwhile to give it a shot at least if the root-stock survives it would come back true from a freeze.
Thanks Mark

It's complicated, took the guy 5 minutes or so to run thru it and I'm not going to remember it all now.  But, he starts under misters, takes the cuttings out from under the misters, they develop some kind of callous bulbous area.  Gives them a high N organic food, drenches them well.  Forgot the name of it.

He also has/had seedlings which he's sold.   

[Mark in Texas]

I had about 6 of the common text mex avocado make it through 13 degrees here in Louisiana with a couple inches of die back. They only had 2mil plastic wrapped around them with a open top 5-6ft tall.

That's damn good.  Believe Austin got down to 5F. They (and me) lost power very quickly, like the first or 2nd day into the ice/snow storm.

[Mark in Texas]

Rooting avocado is not that easy. Looks like I finally have one avocado cutting that is growing leaves but I will need to wait another month to know for sure if its got roots. I don't want to disturb it now since it's the only cutting that I planted that has not dried up/died this year. I must have tried rooting over 80 cuttings this year and so far only 1 looks good still.

The owner of this stock has a beat a huge challenge - making sure the rooted cutting holds all the new leaves on for a long time.  I couldn't believe it and replied "you know avocados have a flush of new leaves 2 - 3 times per year with a total loss of those that hung on during the winter and drop during the new spring flush."

Tree defies all logic!

BTW, it is NOT a knockoff of Tex-Mex trees sold in local nurseries.  Custody goes back to the 70's originating in south Texas at an older couple's house that were into exotic tropical trees.  They sold the house.

His 7 year old tree in Austin produces 100's of fruit.  I've asked for some fruit when it fully recovers and resumes it's growth.  Like me that means a set back of about 2 years from now for a crop. 

[Mark in Texas]

Sorry forgot to ask can you give us the details on his rooting technique? It might be worthwhile to give it a shot at least if the root-stock survives it would come back true from a freeze.
Thanks Mark

Yeah what’s his method?

Also what about fungus resistance?

I brought up the issue of thin skinned avocados being susceptible to anthracnose.  I think he said it's not a problem.  I need to ask again.

[Mark in Texas]

The tree was undercover and heated probably with a heating cable that means it had a microclimate, then it should survive. To be truly cold hardy should be expose directly to that temperature.

Lost power after day one.  No heat, no protection.

[linsecte]

Hello,
i would like to make some exchanges in order to comparate (in the same place to be sure witch one resists or tolerates better). in my forest, crash tests are every winter: i am 400M altitude in aix en provence, much colder than marseille (france).
i have wilma, joey, aravaipa (these 3 from graft), and others cold-hardy varieties from seedlings. but i miss the chili avocado, such as austin, and fantastic.
i also have unknown varieties from moutains, 600M in france and 1300M in spain. i gave cuttings to someone grafting inside, and sow in my place outside. first results to see next frosts...

[Mango Stein]

The tree was undercover and heated probably with a heating cable that means it had a microclimate, then it should survive. To be truly cold hardy should be expose directly to that temperature.

Spent 45 minutes on the phone with the vendor that has been working with this 40 year old tree in S. Austin.  It took days of below 12F temps (11C) and below.  There was some die back.    Really an incredible story including his technique of getting 50% rooting takes  of cuttings.  Parent tree is 35' tall with a 4' girth trunk.  Says the fruit is very rich.   

Just for the record, 12 Fahrenheit is actually -11 Celsius