Interesting Story about these two cold hardy avocados.

[OCchris1]

I admire your dedication Joe! Your ability to process the literature and come up with your own ideas that could work in your environment is commendable. Well done.

[Mark in Texas]

  I've heard nothing but good things about the Mexicola.

Im here to say bad things about mexicola. My mexicola has a date with my chainsaw coming up. 

You're spoiled and with what perfect conditions you have I don't blame you a bit for being damn choosy.  It's been reported that an old Mexicola in one of the southern states took 5F and survived.

I guess everyone has their preferences for rootstocks.  I found the typical Florida Slimcados, the W. Indies X Guatemalan hybrids like Monroe, to be extremely vigorous and accepting of scions.  My original trees done back in 2012 are on those stocks.

[Mark in Texas]

First I did research on where the cold hardiest oldest trees are found and when they bear fruits. So during the fruiting season, I looked at the forecast if it is windy. If that afternoon to evening is windy, I schedule a very early morning trip to those trees and then pick up their fruits from the ground. Most of these trees are in public parks and if on private properties, some of their branches extends to the roads and so I pick up the fruits, and I ripen them, got to taste them too, and then use their seeds as rootstocks.

Now I have many cold hardy avocados grafted on to those seedling rootstocks and as they bear fruits, I use the seeds to experiment if they make excellent rootstocks. I usually started them by germinating them during the winter on potting media, and left outside. I have produced many cold hardy seedlings this way. I will have plenty to experiment from my first generation fruits.

Damn, that's what I call passion.  Good on ya!   If I wasn't getting too old for this chit I'd reinvent the wheel with Nuevo Leon and Oxaca Mexican Criolo avocados, growing and selections. I have a connection thru a friend who knows a Mexican avocado grower who grows and sells varieties of the old landrace Mexican cold hardy Criolo avocado trees.  He's offered my friend scions.  i backed out of her request to graft different named varieties due to the risk of customs and other issues such as disease/insect contamination, which I guess you could get around with a quarantine drill.  She would basically have to smuggle them across is what she's telling me.  Here's one such avocado hanging from one of his trees.  These Mexican and Guatemalan avocados come in all shapes in sizes from ping pong ball size to 2 pounders.



Here's a partially censored variety script he sells beginning with the words "Tengo...." aka "I have....."



I wonder what his "egg of the bull" variety tastes like.   

[JoeReal]

First I did research on where the cold hardiest oldest trees are found and when they bear fruits. So during the fruiting season, I looked at the forecast if it is windy. If that afternoon to evening is windy, I schedule a very early morning trip to those trees and then pick up their fruits from the ground. Most of these trees are in public parks and if on private properties, some of their branches extends to the roads and so I pick up the fruits, and I ripen them, got to taste them too, and then use their seeds as rootstocks.

Now I have many cold hardy avocados grafted on to those seedling rootstocks and as they bear fruits, I use the seeds to experiment if they make excellent rootstocks. I usually started them by germinating them during the winter on potting media, and left outside. I have produced many cold hardy seedlings this way. I will have plenty to experiment from my first generation fruits.

Damn, that's what I call passion.  Good on ya!   If I wasn't getting too old for this chit I'd reinvent the wheel with Nuevo Leon and Oxaca Mexican Criolo avocados, growing and selections. I have a connection thru a friend who knows a Mexican avocado grower who grows and sells varieties of the old landrace Mexican cold hardy Criolo avocado trees.  He's offered my friend scions.  i backed out of her request to graft different named varieties due to the risk of customs and other issues such as disease/insect contamination, which I guess you could get around with a quarantine drill.  She would basically have to smuggle them across is what she's telling me.  Here's one such avocado hanging from one of his trees.  These Mexican and Guatemalan avocados come in all shapes in sizes from ping pong ball size to 2 pounders.



Here's a partially censored variety script he sells beginning with the words "Tengo...." aka "I have....."



I wonder what his "egg of the bull" variety tastes like.   

The egg of the bull might just be the shape and size. After all, the original word for avocado is 'testicle'.  Nahuatl name for the indigenous avocado fruit is āhuacatl, that also means “testicle.”

That would be interesting... All those cultivars.  All of the avocados that the US have were originally smuggled in from other countries, mostly from South America and Mexico. The endemic ones were from seedlings of the smuggled ones of ancient days. When US was not yet formed, people from Americas moved about and brought with them plants and animals. Of course those that have established avocado orchards wanted protection.

I don't know of any existing quarantines on avocados, since they're not a major agricultural crop of the US.

 

[Mark in Texas]

The egg of the bull might just be the shape and size. After all, the original word for avocado is 'testicle'.  Nahuatl name for the indigenous avocado fruit is āhuacatl, that also means “testicle.”

That would be interesting... All those cultivars.  All of the avocados that the US have were originally smuggled in from other countries, mostly from South America and Mexico. The endemic ones were from seedlings of the smuggled ones of ancient days. When US was not yet formed, people from Americas moved about and brought with them plants and animals. Of course those that have established avocado orchards wanted protection.

I don't know of any existing quarantines on avocados, since they're not a major agricultural crop of the US.

You know your testicles well.   Mexico is a bit weird regarding bringing avocados back across the border.  You can do it but for some strange reason the vendor must remove the seed upon the sale.

Here's one Mexican avocado grower in case you do Facebook. https://www.facebook.com/jaime.gonzalez.900388?__tn__=%2CdlC-R-R&eid=ARBq9MEg4CRtHJaQJV-ERVkTV_slqF8oh7bRQ2MRH5L4FJoDe_suzTDFllJ2JlJpx6r-kqTnTWzh7Opg&hc_ref=ARSm137MJLu4gTrAkjARILAiA71ufnyzZqxSxexNBpL13CJTcMxN28eFYVBo1NWflZw

This Texan lives near San Antonio and has quite a few videos including taste tests of varieties he grows.  Does very well with the Tex-Mex avocados some growing as big as 30'.  https://www.youtube.com/watch?v=TvpI9x9wG_Y&feature=youtu.be

[ricshaw]

Genetic Diversity of Mexican Avocado in Nuevo Leon, Mexico

https://www.intechopen.com/books/molecular-approaches-to-genetic-diversity/genetic-diversity-of-mexican-avocado-in-nuevo-leon-mexico

[ricshaw]

Genetic Diversity of Mexican Avocado in Nuevo Leon, Mexico

https://www.intechopen.com/books/molecular-approaches-to-genetic-diversity/genetic-diversity-of-mexican-avocado-in-nuevo-leon-mexico

I learned something new: 
"Persea americana var. drymifolia trees are characterized by their resistance to cold and
high oil content, a very distinctive characteristic is its strongly aromatic leaves (anise scented)
in almost all individuals; usually, they grow at altitudes greater than 2,000 m. The leaves are
dark green with light green or reddish young shoots; the fruit has a thin, smooth and soft skin,
the seed can be adhered or loose, the cotyledons are smooth or slightly rough, and it is common
to find fibre in the flesh, although this is not found in most cultivated species.
Given that the avocado is an open-pollinated species, it contains great genetic variability with
almost unlimited possibilities for utilization; a wide diversity of germplasm allows the
advancement of botanical and agronomic knowledge and the development of new cultivars."

[Mark in Texas]

Genetic Diversity of Mexican Avocado in Nuevo Leon, Mexico

https://www.intechopen.com/books/molecular-approaches-to-genetic-diversity/genetic-diversity-of-mexican-avocado-in-nuevo-leon-mexico

That's where my friend's friend lives - state of Nuevo Leon.  I noticed some of the improved creoles is what he's growing. 

I would think that if they grew, shipped, and warehoused well, had a good meat to seed ratio, they would be grown in place of Hass. 

[ricshaw]

I would think that if they grew, shipped, and warehoused well, had a good meat to seed ratio, they would be grown in place of Hass.

Thin skin and different appearance... probably not going to replace Hass.

[z_willus_d]

Nice to see some success in my area. I'm actually pretty close to some GIANT duke's in oroville.
Did you plant in a mound or directly at ground level? I know standing water is a huge issue out here.

Joe, excellent and extremely interesting (and to me) important work that you've presented.  I've been on a similar, if less sophisticated and successful, quest to successfully grow avocados here in Sacramento (Roseville suburb), where we often see the wild temp drops, particularly with these artic inversions we've been getting of late.  I came upon the Duke story (and even held dialogue with it its progenitor and others related to it).  I've made several trips to Oroville to take cuttings and search for seeds.  I've only found one half-eaten avocado from in my visits.  The 2nd set of cuttings I took were grafted onto 2 or 3 box store 5G trees I purchased.  The trees were not healthy due to the winter they withstood, and wild several of the grafts took, the trees ultimately died.  I'm now banking on my Fuerte, Mexicola, and Bacon to survive the transplant I just subjected them to in my front yard.  These trees just produced their first fruit (the Mexicola was excellent) last year.  I had them in large ~50-gal containers for 5+ years.

At any rate, I'll be following your work very closely.

Thanks for sharing.
-naysen

[Luisport]

I just found ettinger avocados on the market. I buy some to plant the seeds... untill now i have stewart, ettinger and sir prize seeds growing. Hope to have more cold hardy varieties soon!

[Mark in Texas]

I just found ettinger avocados on the market. I buy some to plant the seeds... untill now i have stewart, ettinger and sir prize seeds growing. Hope to have more cold hardy varieties soon!

Ettinger, a B type, is supposed to be pretty good. Big seed, creamy flesh.  It's one of many that was trialed in S. Texas by TX A&M before an arctic front nailed the orchard.

[Luisport]

I just found ettinger avocados on the market. I buy some to plant the seeds... untill now i have stewart, ettinger and sir prize seeds growing. Hope to have more cold hardy varieties soon!

Ettinger, a B type, is supposed to be pretty good. Big seed, creamy flesh.  It's one of many that was trialed in S. Texas by TX A&M before an arctic front nailed the orchard.

Well we are not Texas... 
At least in my location is very rare to have temp below -3C. 3 years ago we got the lowest ever temp of -6,5C and my bacon avocado survived. Both reed and hass died. So i think ettinger will do well. I Have seeds of stewart and sir prize growing and will have more cold hardy varieties soon, so i'm optimistic... 

[barath]

I remember Julie Frink being unimpressed by Ettinger.  It is a Fuerte seedling, but apparently isn't as good tasting as Fuerte.  (I planted one for a friend years ago because he wanted one, but I think his climate was too foggy for it to ever produce.)

[Lionking]

Nice to see some success in my area. I'm actually pretty close to some GIANT duke's in oroville.
Did you plant in a mound or directly at ground level? I know standing water is a huge issue out here.

Always plant elevated from the ground in most areas of California. I recommend at least 3' x 3' x 1' high planter box (made of retaining wall bricks preferably).

Hey Joe,

    So what are you filling the planter box with?  What amendments are you using?
Reason I ask is that I just finished building a planter box for my slope.  I built a 4x4x36”.
My soil here is very rocky.  The top 1’ 6” is sandy loam but after that it’s  hard compacted clay.
Water does not drain well.
I already dug down the 3’ for the planter box and I also dug a hole in the middle of the box another 2’ plus.
I plan on adding some rock to allow water to drain down.  Then I dug a hole from the side of the slope into the bottom of the hole in the center of the planter.  I plan on inserting a piece of 3”  pvc pipe for drainage.
I will be planting 2 avocado trees in this planter.  An A type and B type.
I have a Gem and plan to add a Sharwil.  If I can’t find the Sharwil, might go with Sir Prize.

[JoeReal]

Nice to see some success in my area. I'm actually pretty close to some GIANT duke's in oroville.
Did you plant in a mound or directly at ground level? I know standing water is a huge issue out here.

Always plant elevated from the ground in most areas of California. I recommend at least 3' x 3' x 1' high planter box (made of retaining wall bricks preferably).

Hey Joe,

    So what are you filling the planter box with?  What amendments are you using?
Reason I ask is that I just finished building a planter box for my slope.  I built a 4x4x36”.
My soil here is very rocky.  The top 1’ 6” is sandy loam but after that it’s  hard compacted clay.
Water does not drain well.
I already dug down the 3’ for the planter box and I also dug a hole in the middle of the box another 2’ plus.
I plan on adding some rock to allow water to drain down.  Then I dug a hole from the side of the slope into the bottom of the hole in the center of the planter.  I plan on inserting a piece of 3”  pvc pipe for drainage.
I will be planting 2 avocado trees in this planter.  An A type and B type.
I have a Gem and plan to add a Sharwil.  If I can’t find the Sharwil, might go with Sir Prize.

There's a local landscape supplier that I purchase garden soil. Their garden soil retains soil moisture but it has very good drainage. They aren't giving me their recipe but inspecting it, it has compost, coconut coir dust and sand. I use them as all purpose potting soil and are also excellent for citruses.

[spaugh]

Nice to see some success in my area. I'm actually pretty close to some GIANT duke's in oroville.
Did you plant in a mound or directly at ground level? I know standing water is a huge issue out here.

Joe, excellent and extremely interesting (and to me) important work that you've presented.  I've been on a similar, if less sophisticated and successful, quest to successfully grow avocados here in Sacramento (Roseville suburb), where we often see the wild temp drops, particularly with these artic inversions we've been getting of late.  I came upon the Duke story (and even held dialogue with it its progenitor and others related to it).  I've made several trips to Oroville to take cuttings and search for seeds.  I've only found one half-eaten avocado from in my visits.  The 2nd set of cuttings I took were grafted onto 2 or 3 box store 5G trees I purchased.  The trees were not healthy due to the winter they withstood, and wild several of the grafts took, the trees ultimately died.  I'm now banking on my Fuerte, Mexicola, and Bacon to survive the transplant I just subjected them to in my front yard.  These trees just produced their first fruit (the Mexicola was excellent) last year.  I had them in large ~50-gal containers for 5+ years.

At any rate, I'll be following your work very closely.

Thanks for sharing.
-naysen

What are the plants in the blue plastic?  Its seeds or trying to root cuttings?

[z_willus_d]

Hi Brad, it's the same plants you see in the two images above in the blue bags. I was just trying to increase humidity.  I've never managed to get an avocado cutting to root with this method.  Works great for Fig, stone fruits, olives, and sometimes blueberries though.  I'm sure someone has a more sophisticated method for rooting avocado cuttings that works with a greater than 0% success rate.

[spaugh]

I think you need to grow seeds and graft them.  Otherwise all the nurseries would be rooting cuttings.

[z_willus_d]

Yeah, I had extra cutting and thought I'd try.  I've heard with air-layering that it's possible, but grafting is the only "sure way" to propagate avocado.

[spaugh]

Even if you managed to air layer an avocado branch, the root system of a seedling is probably much better.  Im having good success here planting seeds in pots, growing for 6 months or so until they are a foot tall, then planting in ground.  Then let those grow a couple more months and gain some vigor then graft them on in ground stock.  The grafts take really easy on trees already semi established in ground vs in pots. 

[spaugh]

If you are going to do them in pots, it seems to work best if you let the rootstock get a couple feet tall and when you graft it, only remove the top few sets of leaves.  The more leaves left on the rootstock the better it works.  At least for me.  I see the pros completely hack off really small seedlings and graft them.  They have a perfect greenhouse and method though.  For us home growers, its a bit harder to get dialed in.

[z_willus_d]

Yes.  I need to find a good source for seeds.  The random seeds from store bought avocados I've attempted to sprout have been hit and miss.  I'd like to get healthy, grafted (to ideal seed/rootstock) Duke, Aravaipa, and maybe one of Joe's "Lynn's Cold Hardy Hass" specials.  I have a couple spots reserved in a raised bed for these candidates.  It would be great to not have to fret so much each winter with the C9 lights and thermal mass heat dispersion assists.

[JoeReal]

If you are going to do them in pots, it seems to work best if you let the rootstock get a couple feet tall and when you graft it, only remove the top few sets of leaves.  The more leaves left on the rootstock the better it works.  At least for me.  I see the pros completely hack off really small seedlings and graft them.  They have a perfect greenhouse and method though.  For us home growers, its a bit harder to get dialed in.

You don't need a greenhouse to micrograft avocado seedlings. Ziploc bags will do. I can graft smaller than these and use tomato grafting clips instead of parafilm. I cover the pot with plastic food bag held by bamboo bbq sticks, secured around the mouth of the pot using rubber band.

[spaugh]

Nice Joe.  Did you ever try doing this and leaving a little leaf on the tip of scions?