<< What kills them the most are the dissecating winds that freeze burn them. >>

Rio -- yes, this makes sense.  Thx.  At some point, cold per se may kill.  But the dormant fig, protected from wind and sun, seems much tougher than many people think.

<< If you can grow fig trees in zone 5, good for you! >>

As Rio said, no offense intended.  It's just that you made a very strong assertion that was inconsistent with what I've observed.  I wouldn't want potential fig growers in the northern U.S. and Canada to be discouraged needlessly.

I grew up on a farm in zone 5, lived in that zone most of my life.
Then I moved to where I am.
The growing season is 3 months longer here.
What I can easily grow here, I would have struggled to grow in ohio.
Those in colder zones, they need greenhouses to extend their season.
Not trying o discourage anyone. Give it a try and see.

Doug

"Just to add,
my father in ohio put all his figs in a unheated garage.
Every single one (15) died.
he gave up trying to growing figs.
Not worth fighting the climate."

I keep 200+ pots in an unheated greenhouse all winter. (NJ z6) I covered the inside walls with rigid insulation. It acts like a giant igloo cooler. I water a couple times in the winter so the pots do not completely dry out. My pots can and do freeze solid. Last winter I did not loose a single tree. Keeping the wind out is #1 priority. It's been said before but bears repeating. The #2 killer is an early warm up followed by a hard freeze.

ADelmanto -- That's great info and a sensible conclusion.  Thx.

Hi,
I've been toying with figs in pots, just to have backups for in case of a harsh winter coming back.
The pots are in the garden-house , no building nearby, no house nearby, the field is (was) opened to the winter. I grew an edge to cut the wind blow.

The pots get frozen solid for 2/3 weeks twice in the winter.
Last year my low was at -10°C/ 5°F (mild winter), and I didn't lose a single tree.
I had one tree in a pot as thin as a 1.5Liters soda-bottle. The pot froze solid, and the tree survived.
If you search on the forum, I have a picture of cuttings frozen in a soda-bottle, and they still grew leaves at Spring time ... But did not root due to my neglect probably.

You should start bothering about temps, when you reach or sink under -15°C / 5°F ...
But under -15°c, wahtever the age of the figtree ... you may be in trouble.
I lost several in-ground trees in 2012 due to temps sinking and reaching -25°c once in a night in February. The age of the tree did not make a difference.
Most of the old fig-trees I knew had to come back from the roots. Of course, some being near building, they got some extra heat from the heating of the buildings ...

Very interesting the comment about wind. A number of the old-timers near me in Toronto swear its the wind and other elements more than the cold that does the real damage. "Freezing" itself doesn't seem to be what kills anyhow. If it was nobody around me would be able to grow figs at all. Growers like Adriano just put potted figs laid flat on the ground with shallow plywood walls. The certainly freeze and come back. 

As noted above though there seems to be a limit that appears to be tied to the variety and age of the tree. Older trees seem tougher and below -15c or -20c watch out...... Some out there claim hardy to -30c. I'd like to get my hands on those trees. 

I doubt you'll find those in named varieties....likely rather in some old neighbourhood being lovingly tended to...

Would like to hear more experience stories after this winter.

I agree with the wind and other elements. I kept figs of all sizes in a detached concrete garage during some brutal years. It was basically the same temp in there as outside never lost a tree. Plenty of nights in the teens. I have even kept trees in a storage unit outside for one winter and they were not effected at all.

Roots hold moisture.
When water freezes it expands.
When roots freeze, the moisture in them freezes then expands.
It destroys root tissue.
If your figs can be frozen solid then live, only proves how tough a plant the fig is.
We do not reach lows like you guys talk about, but I have had a young tree freeze
to death, even in my climate where we do not get to -15.
Let em freeze, only a few die.


Doug

This is interesting. I have no illusions that -30c will kill a fig tree. It'll kill most things..... but in this post we're talking about "freezing". My attached garage wont ever hit -30c or even -15c for that matter. But -5c and a bit lower isn't that uncommon. I know many who successfully overwinter the same way. Be it in a garage or buried.

Last I checked -5c (23F) is still very much frozen. These trees are freezing, roots and all. So I wonder what the difference is "between" freezing and "freezing to death"?

<< when roots freeze . . . . >>

Doug --

Dormancy reduces moisture in roots and branches.  So it takes lower temperatures to cause a damaging freeze in a dormant plant.  

Variations in damage to roots would seem to depend on:

1.  How dormant is the fig tree?
      a.  How readily does the variety shed moisture in preparation for winter?  This may be one major variable determining cold hardiness.
      b.  How well did growing conditions help prepare the fig tree for winter?  For example, was it consistently 50-60F or 30-40F before temperatures dropped to 20F?  

This may be the bigger issue in warmer growing areas like yours.

2.  How cold is the soil?  The earth is a huge heat sink.  It takes consistently cold weather to lower soil temperatures much below the surface because warmth is continuously migrating from deeper levels.  So one day at 0F may be inconsequential for soil temperature; one week might matter.

This may be a bigger issue in colder growing areas like mine.  

Of course, a pot stored in an unheated garage doesn't benefit much from the relative warmth of the earth.  But given observations of growers who store potted figs in unheated garages, it seems that the roots of fully dormant figs might be able to tolerate temperatures approaching 0F.  

Freezing branches to ground level will likely re grow. froze
Freezing the root ball turned the roots to mush. That did not grow back. dead


Doug

This is very much what I'm interested in - The potted trees in my garage (roots included) are definitely reaching temperatures of at least -5c (23F) and often stay there for some time.... Are you suggesting that they're not frozen? In this environment not only do the roots survive but the existing growth as well.

Seconding what TorontoJoe says, the potted figs in my friend's unheated detached garage must get down to ~10F or lower when the outside air temp is -15F, which is a level reached last winter.  Yet in April, I bought one each of the following from her -- Takoma Violet, Sal's EL, Brooklyn White, Nordland, O'Rourke, and Smith -- once she had unpacked them from the garage.  Not only did they all thrive but they all also produced ripe figs.

Was it not cold enough for the branches or roots to freeze?

Freezing can kill a tree with green growth because it is full of water, but one that stopped growing sooner and is lignified will be fine. Only fine roots will be damaged by light freezing, and they regrow quickly in the spring. Prolonged freezing temperatures can cause containers to "freeze dry", especially fabric containers.

But if if the container is totally soaked (like a container left outside where the drainage holes are frozen shut and melting snow or rain fills it up, or overwatered) it will turn into a solid block of ice and can kill large roots like Doug said. This can kill even hardier container trees like apples or blueberries.

Hmmm....this is what I'm trying to reconcile in my head...(ALL SPECULATION) I'm starting to think it's all about how we define "freezing". OK - So we do away with the idea that "freezing" isn't the problem if we're talking about the general acceptance of what freezing means. That is when water becomes a solid - below 0c (23f).

We also are very familiar with fig trees that will withstand sustained temps of well below this with no damage whatsoever. (branches and root). So to many fig trees that's not freezing. The question is why?

Does a tree maintain an  ability to flush out a level of water during dormancy to prevent damage, yet remain alive? ....A tree more successful at this being one that is more cold hardy?

or perhaps...

The liquids in the tree (sap not all water) have some natural sugar or other content that in effect behave like an antifreeze (Sugar is an antifreeze), keeping the trees moisture from freezing up to a specific temperature below the freezing point of water? So a tree with more of this quality would survive colder temps and those without would not...Just like at -40c even your car antifreeze, freezes

I base nothing I write here on fact or research....just thoughts....

TorontoJoe -- The questions are well put.  Now we need someone who actually knows something! :)

Thanks Joe. The fact is that I'm more speculation and hypothesis than knowledge. I'm still pretty new at this.

I think there's a lot of wisdom on this forum. For me it's a lot of trial and error combined with the experience and experience gained from all the contributing posts....And then more trial and error....

I'm glad this forum exists. I've read mostly sound advice. Like with anything in life there's usually more than one way to do something.

I wish I had more trees with which to experiment come spring. Maybe next year..... None of my theories seem to illustrate to me why a young tree would be more hardy than one more mature....Like a child it has more sensitive tissue? More antifreeze? I don't know....

Joe

Here you go guys.
http://www.planetfig.com/articles/fareng2589.html

Really good article. "resin and carbohydrates". That's making a lot of sense.

Thanks

TJ -- I didn't mean to imply any put-down.  I'm in exactly the same boat as you, just trying to learn from our collective experience.  I appreciate your observations.

from the linked article:  

< In fact, it would be normal to consider that young and vigorous fig plants may be damaged or completely killed by ground frost, when temperatures drop to between -2 and -4°C. 

On the other hand, if it benefits from protection during the first years and succeeds in developing, the fig tree may easily resist temperatures of between -15° and -17°C, and even less for some varieties, when planted in very good locations (-18°C at least). >>

So assuming that this is correct, here is the paradox -- young / non-dormant figs will be killed at -2 to -4C (23 - 28F); older, dormant figs can survive -15 to -17C (1 - 5F) our even lower for good varieties in good locations (0F "at least").  

The words "may easily resist" seem optimistic.  But basic point seems right, given observations here.

One last point:  The article points out that the amount of water that a fig receives late in the growing season impacts its vulnerability.  So we should all interpret our experience through the lens of water received or applied, naturally or artificially.   

Every fig planted in ground would apparently benefit from a stone or brick and mortar "clamshell" windbreak half surround and solar heat sink to protect, capture and then radiate heat back to the plants. We have seen evidence of the apparent benefits of a radiative wall or stone outcropping to one side of an in ground fig; perhaps when considering planting, one should consider such landscape enhancements as basic requirements. I would imagine that even a low espalier planting could benefit during winter from benefits of a heat sink type brick or stone backing running its length...