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View Full Version : Experiment: How much cold can a banana take?


Olafhenny
10-30-2013, 10:01 PM
This is actually a follow-up on this thread: http://www.bananas.org/f10/interesting-not-yet-19145.html But because it deserves
broader attention than it would get if I posted this there, I am starting a new thread.

Last night was the third time my bananas were exposed to frost this fall as well as the coldest
so far.

Here is, what they have been exposed to:



http://www.bananas.org/gallery/watermark.php?file=55075 (http://www.bananas.org/gallery/showphoto.php?photo=55075&ppuser=7269)

The temperatures were recorded at our local weather station, which is located less than
1km (1/2 mile) from my bananas.



http://www.bananas.org/gallery/watermark.php?file=55076 (http://www.bananas.org/gallery/showphoto.php?photo=55076&ppuser=7269)

This is my biggest pad. You can see, that it is severely nipped by frost, but the PS is in no
jeopardy yet.



http://www.bananas.org/gallery/watermark.php?file=55077 (http://www.bananas.org/gallery/showphoto.php?photo=55077&ppuser=7269)

This plant, more sheltered (protected by >10’ high canna New Zealand), is even less affected



http://www.bananas.org/gallery/watermark.php?file=55074 (http://www.bananas.org/gallery/showphoto.php?photo=55074&ppuser=7269)

This little guy, completely exposed, still has no problem at the PS level.


The last plant is actually quite a bit older, than the one in the third picture and is the one,
I have mentioned in other posts as left virtually unprotected last winter. As a consequence
it froze or rotted down to 2 inches below soil surface and consequently took a looong time to
recover in spring, a prime example of the delay caused, when there is no above ground section
of the PS left. Admittedly being choked by the surrounding vinca major did not help. However,
I kept that at bay for quite a while in spring, to give the emerging basjoo a chance.

Foot note: The above pictures were all taken at about 2 pm after the leaves were well thawed
out and any damage to the cells would show up.

Richard
10-30-2013, 11:59 PM
Here in the U.S. we are mostly confused about the meaning of "frost" and "freeze". So "frost" is something that can appear on objects and plants around 4.5C (40F) or lower, and freezing is something that we all agree happens at 0C (32F).

So when you said "subjected to frost", you meant ... ? If it was freezing temperatures, then wow, the plants held up very well.

I know you've cut leaves etc. of banana plants before, so your aware of the "holding cells" of water in the plant, not to mention the overall high density of fluids throughout the plant structure. When that freezes all the way through for any significant time (1+ hour), the biology is in serious trouble.

So how much cold can a banana take? It's an experiment in cryogenics!

Olafhenny
10-31-2013, 12:49 AM
The temperatures in the time schedule should leave no doubt, as to which temperatures
these banana plants have been subjected to and for how long. For those not familiar with
the Celcius system I also added the temps in Fahrenheit :)

They should however not be considered safe, as, if these low temperatures had lasted long
enough, they would clearly have destroyed the PS as well, given they had time to penetrate
deeply enough into it. As it turned out the warm daytime temperatures that followed halted
and reversed any penetration.

When there is frost, things freeze and when the frost is cold enough and lasts long
enough, the lakes and ponds freeze up and the frost penetrates deep into the soil and
kills your corm. It does all that in Canada and even in the US of A as well as China. - No
respect for international borders. Providing there is enough humidity in the air. frost can
also settle on leaves, twigs, power lines and all things thin enough, that they cool down
quickly, so that ice crystals can form on them as the moisture is released from the air. :)

Abnshrek
11-17-2013, 11:03 AM
I don't think all banana's are the same and comparing them or generalizing the subject isn't going to help a new person. Basjoo & Orinoco are in a class by themselves where as Cavendish's, Reds, Veinte Cohol, (and Plantains from what I hear) can get taken out by a good cold spell, and a hard frost is going to get the leaves. Someone might get lucky and have a light burn the 1st day but the 2nd time leaves are toast. I am not using any plastic this year around my Banana's we'll see if that helps. :^)

Olafhenny
11-17-2013, 12:40 PM
Hi Migael,

I believe that the hardiness of bananas pertains strictly to the corm, Which is rated HZ5
in basjoos. However the leaves freeze off at temperatures experienced in HZ 8 or 9.

With the corms it is a different story, and here, I am not sure, It appears, that prolonged
exposure to cool, not necessarily freezing temperatures will rot the corm (and these temps
will vary in accordance with variety). This has clearly not happened in Janet’s case in the...
http://www.bananas.org/f311/little-greenhouse-enough-few-freezes-19437.html#post234211
...thread, since that corm sprouted 2 new pups.

Accordingly we were dealing there with a case of leaves freezing off and that will take
crystallization of the water (sap) therein. That again requires temps in the range experienced
in the experiment in this thread. Another factor is, of course, exposure to wind, which can
speed up the freezing process. But in any case subfreezing temps and time are required.

The problem with this forum is, that it does not lend itself to long dissertations, which
include all eventualities. People who have followed my posts will attest, that they are
lengthy enough as it is. :ha:

lmswayne
11-21-2013, 06:30 PM
I love to read your prolonged diatribes I get good info and a good giggle. :ha: I have found the use of frost cloth to have gotten my bananas through many winters with no die back.

Olafhenny
11-21-2013, 06:47 PM
I love to read your prolonged diatribes I get good info and a good giggle. :ha: I have found the use of frost cloth to have gotten my bananas through many winters with no die back.

In HZ 8/9 :ha:

lmswayne
11-21-2013, 07:35 PM
OK you got me. My high today has gotten to 40F am much wormer :ha: I would freeze where you live much less my bananas. It is very pretty up there and worm in the summer when I have been there. But I have to say I stay away in the winter.:2738::ha: