As of now I have fifty one fig trees of various sizes.  Reality of winter is closing in and no way they can be simply stored in the garage in their current pots.

Our garage is part of the house and is used daily, door opened/closed multiple times per day.  Arkansas weather fluctuates a lot.  We may have several days or weeks in the upper 70's F during the middle of winter.

So taking many variables into account and looking ahead to next spring, the plan then being to re-pot all and use the rain gutter grow system, this is about my best option.  To bare root or semi bare root all as each goes dormant and store them in a huge foam chest where the temperature can more easily be kept at a constant.

A co-worker gave some one inch thick, 4' x 8' styrofoam sheets.  This is the final result.

 

 
It's 3ft x 5ft and 28 inches tall inside.  My tallest fig tree is 23 inches.  Should not be any problem to put all inside. Thinking a layer of moist peat in the very bottom, some to cover the roots and kept slightly moist as required with a spray bottle.

The lid is double layered so the bottom of it fits snug inside while the very top overlaps. Seams are all glued and the screws are kind of useless other than holding it together while constructing.

Plan to install a thermometer to monitor inside temps and rig for a small light bulb in case of extreme cold.  In the event of a warm spell I figure there will also be room to put frozen water bottles to keep it cool inside.

Thoughts?   

I would make a simple frame of 1x2 to add a bit more structure. Then you will be able to slide it without risk of tearing anything off.

What do you plan to do next winter?

I agree with Calvin.  Do something to secure the foam, maybe even build a thin plywood box around it.

I've never barerooted trees for storage.  It will be interesting to see how it works for you.

What is that beautiful wood above your "cooler" in the 2nd pic? 

Sliding won't be an issue since the canoe is moving from its spot.  That is where the chest will be.  Next year?  I can't think that far lol.

A nice greenhouse has been on my want list for a long time.   When I say nice I mean it will have to withstand high winds and big hail we have with spring/summer storms.  Every single cheap poly covered greenhouse I ever made was demolished by winds.  So the last one was wood frame on the back patio with a corrugated material I had to order that was supposed to be strong.  A hail storm decided to test it and won.      

Charlie. A shade structure can be built over a greenhouse to help protect it from strong wind and hail. It does add cost to a project though.

Charlie, this is what I constructed last year, to use for rooting. In fact, I built two.
I keep them in my unheated basement, which lingers at about 50 degrees.
For light (and heat) I use a two-bulb, 4' t-5 fluorescent fixture in each, suspended from the rafters
with jack chain, and poking through the lid, and each fixture is suspended some 4" below the lid. This setup keeps the environment at 70-75 degrees, and fairly steamy.
I have to air them out everyday.
I also agree that you should add some ribs to that box so it won't bulge and blow apart.
Be extra careful with the light source. Make sure there's a drip loop below the fixture to keep
moisture from live parts, and keep the fixture a couple of inches away from the foamboard. That stuff is highly flammable
and noxious.
Get yourself a little fire extinguisher and a battery operated smoke detector, a timer, and you should have a three prong extension cord, plugged in to a GFCI outlet.
Set it to only run when someone's home for the first couple of weeks.
Don't hesitate to reach out to me if you want to talk more about your setup in private.

Rui I think you have misunderstood my intent but thanks for your input.  This box is only to house bare-rooted dormant trees that are for the most part very small, inside the garage during winter.  There will just be a small amount of damp peat in the very bottom.  

If it's sealed well and moist do you think mold would be a problem?

Hey Rich I don't know.  Maybe this mold that's been attacking my cuttings doesn't like the cold.  We'll see.  

Hi Charlie,
A closed space is ideal for mold .
I would make some draining holes at the bottom of the box for any liquid to flow outside of the box.
I would dry the stems - that is remove each leaf and figlet from the trees before putting them in and let the dirt around the roots dry a bit.
Good luck !

Hey Charlie

I agree with Jdsfrance that mold would likely be an issue if the box is not vented .
there should either be vent holes it top and bottom or leave openings at the seams .
I also would not put foam on the bottom of the box , this will allow the garage floor to help regulate the temp in the box .
I did something similar but outdoors and on a larger scale and posted pics and results here ;

http://figs4funforum.websitetoolbox.com/post/figloo-update-5040799?highlight=figloo&pid=1280174529#post1280174529

John

Ah yes John's famous Figloo!  I like that a lot.  Ok I will heed the expert advice.  Had not thought of leaving the bottom off and the concrete garage floor will be plenty cold for sure.  I'm more concerned about the mild spells we have during winter and the trees trying to break dormancy too soon.    

Thats why i would not insulate the bottom , it will keep things cooler on those warm days .

John

I don't think the foam is thick enough, I had stuff inside an igloo cooler in a detached garage freeze solid last winter....anyway, if the plants are that small, why not just grow them on a sunny windowsill this winter....they will get additional months of growing and really won't produce a crop next year anyway...just a thought.....I do it with all my small trees

Charlie, you need one of these.... 

   

Yeah Dennis those top shelf are about the size of most my trees.  Nice setup.  

My garage is attached.  Some very small ones like the tissue cultured and cuttings recently rooted will overwinter inside under lights. 

Ya'll were correct about the mold and I think it was caught just in time.  Even though I cut big holes in the bottom and left the top cracked open, mold had started on some parts of some, but not all.  Discovered this while inspecting for moisture.  Plants sitting right outside the box, all around it have no mold at all.

So the box was dis-assembled.  All are grouped under the canoe on the concrete floor.

On another note, the pots with crushed oyster shell mulch are holding moisture very well and have not needed to water at all, the ones with light mix and no mulch get watered a bit every couple weeks as they dry out a couple inches by that time and the ones with pine bark mulch have only needed one watering since storage.