The winter of 2013-2014 was a winter to remember.  Many fig trees were badly damaged or killed off by the brutal winds and frigid temperatures. 

So my questions are:

1.  What can we do to prevent this damage from happening again?

2.  Will products like: "WILT-PRUF' and other anti-transpirant products help prevent desiccation,
     consequent burning, and die-back caused by frigid winds?  The effects of these products need to be
     observed by us fig growers as a possible way to help prevent some of the problems that the winter
     brings to cold-climate growers.

If fig growers have used "WILT-PRUF" please let us know if this antitranspirant helped prevent die-back.  How was it applied, and at what dilution rate.

3.  Heat sources for storage spaces.  What kind of heat source is effective, safe, and energy-efficient? 
     Electric heaters, heating pads, how are heat sources controlled, etc?

Note: 
I am particularly interested in using anti-transpirants to help prevent die-back and other damage.  I called the "WILT-PRUF" techs. and was told that this product is safe to use on fig trees, and to dilute the concentrate at 10:1, and in some cases, to try a 5:1 dilution rate.  I want to sponge it on and coat all the branches and trunks on my fig trees before they go into winter storage.  It can also be sprayed onto the trees, but sponging it on will be less of a mess in my case.  I'm thinking that grounded  fig trees might benefit from this treatment.

So I would like to hear suggestions, comments etc.

Thanks,
Frank


EDIT:  The now defunct, Paradise Nursery suggested that fig trees could be sprayed with "WILT-PRUF" or to use a Dormant Oil Spray.  I never used either....so, what's the story with these products?  Will they be effective?

There were a couple of threads on winter storage and heating options discussed last fall on the forum. I like to use those blue plastic 33 Gallon barrel filled with water and a farm water trough heater for keeping the figs protected in the shed. The thermal mass of the warm water acts as a radiator and the higher end water pail heaters I feel I far safer than higher wattage heaters for garages. I also wish to keep the temperature above 25, not heat the shed and promote growth. The only issue I have had is that the shelter and "smell" of the heat in the dead of winter attracts rodents so they need to be managed accordingly!

Frank,
Maintaining the storage temperature between 30 deg and 40 deg F. will not only prevent cold damage, but will ensure that the trees remain dormant. Insulating the storage space and providing a simple thermostatic controlled electric heat source (small personal quartz heater and separate thermostat) may be all that's necessary for winter protection of dormant fig trees.

I've never used Wilt-Pruf and have also considered using a sealer to prevent dessication. I've used 100% latex water based paint and Asphalt driveway sealer as bark sealants (both diluted 50% with water), I also use asphalt based pruning sealer for most pruning cuts on fig trees, resulting in healthier growth near the sealed cuts. A major consideration would be that the sealer on the bark may prevent the tree from going completely dormant and will keep too much moisture in the limbs, leading to more damage if the ambient storage temperatures fall below freezing.

How about some outdoor style protection? Maybe insulation plus tarps, like I use on my outdoor trees. Always works for me even this winter, no die back.

My understanding is that Wilt-Pruf, etc. work, but only give you an additional 2-3-4 degrees of protection, say from 32 down to 29. It works in margina areas and areas with light frost or occasional temps just at or below freezing.

Another question comes to mind: 

WHAT actually causes die-back?  Is it caused by desiccation from wind, from cold, from lack of moisture in roots before dormancy, a combination of these three things?  I think die-back happens  because the roots can't replace lost moisture that evaporates from the branches and other tissue.  It seems to me that covering trees with windproof tarps, or a shed, only protects from the freezing winds, and not the cold, unless there is a heat source involved.   Wrapped trees may only be a few degrees above ambient temps.  Die-back has to involve some sort of desiccation event.

I am tempted to try 'WILT-PRUF' on my trees when weather turns cold once again, and trees are dormant.  Trees will then go into a shed come this Autumn.  I will also read about Dormant Oil Sprays and see what these products do.

Thanks for the interest.


Frank

I think I will use one one of these next year and connect it to an indicator light or connect it to the kerosene tube heater or maybe an electric heater now that I will have more power available in the garage this summer.

http://www.thermocube.com

I found that if I heat the garage up to 50f or so it will stay warm most of the night and until it warms up in the morning. I was able to keep my garage above 20 all winter. I see a lot of the French figs sites say (-15c) 5F is the minimum for fig trees. I'm not sure of that in ground or potted or both

Rich,

They do work, have a friend that uses those connected to a string of old time Christmas lights to protect his young in ground orange trees.   

Of those ThermoCubes, do you think the one that tries to maintain above 20 degrees (connected to some electric heat source) is adequate for fig protection in a shed, where the figs will be in pots with no other thermal protection?  Or should you go for the one that keeps temps above 35 degrees?

Citrus growers cover their orchards with water,sprinklers, just as temps drop to freezing. The ice covering protects the plants form wind and actually insulates the trees from cold damage. These temps usually last for hours but sometimes a few days.after it warms up the ice is watered off the plants . Fig trees can have a better chance if planted in the ground where temps of roots do not freeze. Top dress the ground with hay, mulch, etc can further insulate roots. Even though the tree freezes the roots on an established tree will eventually push out another tree,,sometimes this can take months or years. Ask an old timer up there how many times that very old tree resurrected . I would examine the rootstock of frozen potted figs thoroughly and if you can find living roots , trim off the brittle and give it a summer to come back.
Blueberries are beautiful and delicious !,
Terry

Terry,

To be clear the ice covering does not protect plants at all.  The ice covering would actually hurt the plants more than if they were ice free.  What protects the plants is the liquid water that constantly is applied to the ice by the overhead sprinklers.  It isn't the heat of that water that does anything it is the heat of fusion, physics....when matter changes to a different form of matter heat is created.  In this case water to ice and ice to water.  The water turning to ice and the reverse releases heat and it is that heat that protects the plants.  If the water were to stop because of a power failure or pump failure the plants are screwed.   I grow about 200 blueberries in 3 beds and have overhead sprinklers just for freeze protection which has to be used at least once each winter.  As long as liquid water is coating the ice the plants won't get below 32.  

Frank,

I am close (Long Island) and had written this before about my protection. Sorry, if this is a repeat.

1). Potted plants about 60 of all types and sizes. These were put in a non-insulated garage, directly on the floor. So far, my only loss appears to be a young Vista.

2). Outdoor protected trees. I wrapped the following way:
a). Regular pink house insulation
b). Burlap
c). Plastic Tarp
d). 1 foot of hay at base

Wrapped around Thanksgiving, unwrapped last week, then re-wrapped, then unwrapped on Thursday.

Results- Atreano and VDB no damage. I did break a VDB tip when I re-wrapped. Panache had about six inches of die back.


3). Outdoor unprotected trees
a) Three feet from house facing south - Celeste, Negronne and Italian Red - no damage
b). Six feet from house facing east - Black Mission and Hardy Chicago - no damage

Hope it helps.

Thanks,

Steve

Wonderful-

Those Thermocube thingies look like something that will work.  The shed that I will heat for the winter months....is tiny, only about 6ft X 8ft.  I need just a small, low-wattage heater, and then, it will turn on only when temps plunge below a certain level.

Thanks for all the good information.


Frank

Frank,

There are also thermostats you can buy that will do the same thing as the thermocube just at a temperature you preselect.

This extra-cold winter has actually been okay for the trees I have stored in my garage. My garage is attached but off to the side and unheated. This is the first year for me where everything stayed dormant all the way through March. It might be a coincidence, but I think the frigid temperatures kept the trees dormant longer.

Wills C, ice doesn't go below 32 f, we turn our water off after an hour, plants do just fine. It's pain to do this at 2 am but it saves the blueberries, citrus and why not figs. We do it buddy, it works great. Every time
Terry

Terry,


Take a thermometer put it in a cup of water and put it in your freezer.....when the water freezes solid read the thermometer.....the temperature inside your block of ice will be exactly the same temperature as inside your freezer which is far below 32 degrees.   Ice has ZERO insulating ability it is in fact a great conductor of cold.  

The process of using water and ice as protection is exactly as I have stated.  This isn't my opinion....this is simply fact.  http://www.ces.ncsu.edu/hil/hil-705.html  or http://edis.ifas.ufl.edu/hs216 or http://msue.anr.msu.edu/news/using_sprinklers_to_protect_plants_from_spring_freezes  http://edis.ifas.ufl.edu/ch182 all universities and all state the way it works the same as I have.  For a easy to read and understand the basics read this one......http://homeguides.sfgate.com/spray-fruit-trees-water-before-freeze-57933.html
 

Wills. Next year I will take pictures of citrus and blueberry flowers if we get another hard freeze, got down to 15 f this year but only for a day or two,,not sure how things do in the North Pole like up pass arkansas. Blueberries had flowered water applied , ice coating for 12 hours, saved the berries and the citrus. I think you and me should team up , with your education and my brains we could accomplish great things. Just kidding
Oh , I live by Dalton, he's got some on your wish, maybe I can fix you with a b day present
Terry

Terry,

Here is a picture of one of my blueberry beds covered in ice:)  You can see the overhead sprinklers keeping that ice wet which actually protects them.  

Ice is not a good insulator plus those puny stems and buds have almost no heat capacity. Even if ice were a good insulator there is really near zero heat to retain.

Think about it this way, to melt ice requires a lot of heat input, right. Of course. So when ice forms there is a lot of heat output. It doesn't seem like that's the case because ice only forms when there is cold air and/or high radiational heat lose. The heat of ice formation is swallowed up by freezing weather. So as Wills states you need constantly freezing water to get constant heat output to counteract the freeze.