Scott --

Just FYI, here is my potted RdB.  It grew from an air layer taken a year ago.  It's now ~4' high x 6' wide, roughly double the size of the original air layer.  Each major (~2') branch holds ~5 figs, while each smaller branch tends to hold ~2.  There roughly 60-70 figs on the tree in total.  Interestingly, couple of weeks ago the tree was starting a greater number of figs, but it dropped them.

My takeaway is that the tree is a strong grower, attractive but spreading -- it can get big.  It is well behaved -- It branches without extraordinary encouragement, and it really doesn't require much pruning.  I have other mature trees (Florea, Smith, Takoma Violet, O'Rourke) that are growing more densely and producing way more figs per unit of space.  But for my taste, this is perfectly acceptable performance from a variety that tastes great.

One caveat -- a number of posters have questioned RdB's cold hardiness.  I THINK that these growers live in relatively warm areas -- California and the U.S. South.  Personally, I have not experienced a problem.  I have a guess about the reason:  I think RdB may be cold tolerant if it is gradually subjected to progressively colder temps, it goes "dormant" and it stays dormant while the temperatures remain cold.  I think RdB may be tender if it is growing -- either in autumn or in spring -- and temps drop suddenly.  The same variety that handles -5 F in February may be killed by 30 F in April or October.

Joe, my experience is from an Ronde de Bordeaux growing in-ground in Maryland zone 7a.  So in a normal Fall it would gradually go into dormancy but, as you know, sometimes the cold weather can kick in before the figs are fully dormant.   I would say its cold hardiness is about average for the various fig varieties I have grown in-ground.  Mt. Etna types, Vasilika Sika (Belleclare), and a few others are superior.  I had mine growing near to an Adriatic JH and the cold hardiness of those two figs was about the same.

Steve --

My main point here is that relative "cold hardiness" may be different in different locations.

Let me start by making it clear that I'm not sure what "cold hardiness" means.  We know that a fig is damaged during the winter, so we say it is not "cold hardy."  But what do we really know?  We can't be sure whether it died from the very lowest absolute temps of ~-5 to -10 F endured in February, from the weeks of less cold but very dry winds that it endured in January, or from the sudden drop in temps to 25 F after a week at 50-60 F. 

I think your fall/winter is about the same as mine in pattern; it's just a bit colder here (RI 6b).  So I'd tend to agree that "in a normal fall it would gradually go into dormancy."  So it's not so much the autumn I'm worried about, here or there.  Also, winter temps here have gotten to -5 F more or less in three of the past four winters, without material damage to my in-ground (protected) RdB.  So I don't think absolute temperatures are the main issue.

It's more the spring I'm worried about.  I had a grower in CA write that his RdBs were killed by a drop to 30 F.  I assume that those trees had already emerged from dormancy and were growing.  Trying to apply the lesson of that observation here, I think that the greatest risk may be in spring, when warm temps tease a tree out of dormancy and then a cold snap kills it.

Last winter, I had roughly 60 trees of 35 varieties stored in the same unheated but attached garage.  The temperature never dropped below 35 F.  Until March, the temperature very rarely rose to 50 F and the trees stayed dormant.  Then in March and April, there was an increasing frequency of days with temperatures 45 F and higher.  What I observed was that some varieties began to grow earlier than others.  Smith, LSU Gold and LSU Champagne, and some others started early; RdB, the Mt Etnas, and some others started late.  

If this apparent resistance to emergence from dormancy is real and if a growing tree is more vulnerable, then the key questions would be (1) how resistant is a variety, and (2) how variable are local temperatures in a range of roughly 25 F to 60 F?  Paradoxically, growers in Z7-8 may be more exposed to variable temps in the stated range than growers in Z5-6.  

That's not to say that absolute temps don't matter.  Another observation of mine was that some varieties, notably Smith, did not seem to lignify  as thoroughly as others.  I suspect that these green dormant figs are more vulnerable to absolute cold than the well lignified varieties. 

Anyway, RdB has been among my most cold resistant varieties, roughly equivalent to Florea.  It has been superior to my Mt Etnas (MBvs and HC) and to Gene's Paradiso.  "Hardy" Chicago is, ironically, the least hardy of these here.

Joe, that's really different from my experience with RdB and I don't have an explanation for why.  It sounds like you may protect your various varieties better than I do but you also have colder winters in terms of the lows.  I will say that over the years I have been growing in-ground I have been lucky and have never had a situation where in-ground figs come out of dormancy and then are hit with freezing temps.  It seems like my in-ground trees here in MD take forever to come out of dormancy.  Other growers in colder zones are showing pics of their in-ground figs pushing out leaves and mine are still snoozing away.  I like to think that I have a longer Fall than they do though.

Anyway, I'll be watching to see how cold hardy RdB is at my new place compared to others - maybe my results will be more like yours this time?

The whole topic is a bit of a mystery to me.  

Last winter was mild.  I think the lows were around +10 F, which is supposedly cold enough to kill unprotected figs.  But the prior spring I had planted an air layer of Gene's Paradiso on the northeast side of a big rock.  As an experiment, I didn't cover it.  It survived with zero damage.  Even the pencil thin new growth was untouched.  

Meanwhile I had given an air layer of Florea to a friend who lives further north.  He planted it in his side yard, fully exposed.  He protected it with only a tarp.  His low temps were probably ~0 F.   The tree suffered ~50% damage but survived.  If I had to guess I say that he suffered the damage because the tarp ended up acting like a greenhouse cover on warm days in spring.  But of course it offered no real benefit during the cold night that followed.

My winter protection is foil-covered bubble wrap, period.  It blocks wind, which just about any protection would do.  It also reflects sun, so it may be better than other materials in preventing premature warming in late winter / early spring.  It's value as insulation is minimal, so I really don't think that it retains much heat.  

I've never seen a scientific discussion of when the emerging tree becomes vulnerable.  Is it when there are leaves?  Swelling buds?  Moving sap?  In any case, I think you are blessed if your trees stay dormant longer -- that keeps them out of trouble.  

Steve, is your RdB the wide leaf version or the narrow leaf version? I don't think the figs are any different from what I have seen in pictures, but there are certainly 2 different types of leaves and people either have one or the other. Mine is the narrow and originated from Herman, I know yours has a different origin. Joe has the wide leaf version.

Calvin -- Thanks.  I wasn't aware that there were two versions.  That might explain some of the variations we've discussed.  Can you post a pic of the narrow?

Mine originated from Danny at Brugmansia-Quebec who got it from Baud.  I suspect it is the longer fingered version but am not sure - let me know what you think.

Newton, when you say that the cold hit before the tree was "fully dormant" do you mean the leaves hadn't yet dropped?

Scott, that is the most usual scenario.  However, even after the leaves drop the wood might not be as deeply dormant as it is later into the winter.

Steve -- Calvin never answered your question.  I rechecked my own RdBs, all from the same mother tree, and find a wide variety of leaf shapes encompassing both variations he noted.  I'm not convinced that there are two RdBs.

Joe D. When you cover your trees with the bubble wrap, do you completely cover them from ground level up with no vent? Or do you cover just the sides leaving the top open or a small vent?

I took an airlayer from the tree shown in post #33 to my new place and planted it in the ground this past Spring.  It seems to me that the leaves have somewhat longer fingers that that shown for the mother tree.  It wouldn't surprise me if this changes as the tree matures.  So I am also skeptical about there being two different strains of RdB but stranger things have happened.

Tony --

The short answer is that I have completely covered, trying to minimize air leaks.  I figured that one main function of the cover is to modulate fluctuations in temperature, and the easiest way to do undo this benefit would be to let the wind blow in, whether cold or warm.  The R factor for bubble wrap is inherently pretty low, but it would drop to zero with any significant air flows.

Some time in March I have generally opened a vent hole, thinking that I might avoid mold.  I don't think this has helped and it may have hurt.  FWIW, I seem to have experienced mold in two situations:  In one case, I had put some ordinary bubble wrap in direct contact with the tree; I'll never do that again. In other cases, there's been mold on tips and branches that I believe were already killed.  I don't think that the mold caused the damage, I think it took advantage of it.

I'm not saying that this was the optimal approach, just what I have done.

Given my comments above about what "cold hardiness" really means, you probably guessed that I have seriously considered using a cover such as you suggest -- one that blocks sun and wind but is sufficiently open to leave the trees totally exposed to cold temperatures.  I did this with some Asian persimmons last winter; it worked but the winter was unusually mild.  

My reservations are twofold.  First, there must be some limit to the ability of a dormant fig tree to tolerate absolute cold.  Let's say that for my varieties, the lower bound is not +15 F, as sometimes discussed, but somewhere around -5 to 0 F.  At the margin, airtight protection might keep the temps inside the cover above that lower bound.  Second, there is risk that warm temps in late winter / early spring encourage an early emergence from dormancy.  Airtight protection might keep the temps inside the cover below the levels that initiate growth.  So both in extreme cold and unseasonal warm, an airtight cover might make a difference.

Wow, this is a lot of great information.  There is something else I was hoping to learn with regards to this comment from the spreadsheet about RdB: "Fruit quality not always good when cold and rainy but when good it's among the best".

Various sources indicate that the taste and appearance of the fruit is highly dependent on the soil, the sunshine, the weather etc. The fig tree that produces the best tasting fruit in someone else's yard may not do the same in your yard even if the climate seems similar. Also, in a single yard, the quality of a tree's fruit can vary from year to year. Based on this, I assume that if a certain fig consistently shows up in many people's top 5 best tasting, that variety must be more tolerant to climactic differences. 

I wonder if anyone has observed RdB, Stella, or Florea to be more temperamental in terms of fruit quality than other cold hardy figs for beginners? Also, am I even correct that some varieties are more or less reliable than others in their fruit quality? If so, it seems that this would be an important trait to consider in a fig tree for beginners. 

Scott

Few figs are good when it's cold and rainy.  Of my varieties, the one exception I can identify is Gene's Paradiso, which ripens good figs in early November if the temperature gets above 60 F -- but is can split.  And also Desert King, which works well in the Pacific NW.

Of these three varieties, my impression is that Florea is the least temperamental / most reliable here.  On the average it is less tasty than RdB, but it produces more figs and, if those are allowed to properly ripen, they are very good.  If you have a "workhorse" variety and a less productive but very tasty variety, which should you choose?  Obviously, both.  As I said above, I don't know Stella.  

But outcomes in New England will be different than outcomes in South Carolina.  There I suspect you will have to worry about hot and rainy.  And your growing season in way longer, so more is possible.  You should think seriously about good figs well suited to the South (e.g., Smith).    

I actually just got a Smith and a few others. If I really wanted to I could just buy them all and see what does the best. I suppose I want to learn about this topic not just because I want help with what figs to buy for myself, but because I want to accelerate my learning about figs. I really like to learn new things, so it's not as much fun if I only find out what works in my area. 

In my yard, Stella is on the slower side for growth (perhaps because it expresses symptoms of fig mosaic virus strongly), and makes fruit that are large but pretty bland.  It's on the chopping block to be replaced with more tasty varieties.

Thanks for the info Joe.
I need to try winter protecting my RDB in a different way than my usual or transplanting it to a new spot since it dies to ground level every winter. It's no fun growing it year after year only to get 3 figs after a year long wait. Good thing I have a potted version.

Tony -- what have you been doing for protection?