Originally Posted by tinyfish
Great idea.

Is the thermostat under the pink insulation?

Have you considered burying that tree.

Originally Posted by ADelmanto
I'm curious about this method. I've also seen where Christmas lights were used instead of heat tape. Basically the same theory. How old was the tree when you put it in the ground? Is this the same tree that grew back from the root? Young trees are certainly more vulnerable to the cold than older ones. I wait 2-3 years (a minimum of 2 winters) before planting my figs in the ground. If this is the same tree than the wood is less than 1 year old. I can't think of a better way to protect a young tree, but as the tree gets older and stronger it may not be necessary. I would think it would be overkill. I've come to believe that a minimum temp of 20 degrees is just fine for most figs. You need to keep the decicating wind off of the tree by wrapping it, but it should not need much more than that. Especially as the tree gets older and stronger. There are certainly exceptions, but try not to plant those border line varieties in the ground.

The only problem I can think of is there may be an issue of the branch of the tree needing water over the winter and the root being frozen and unable to provide it. I've seen this problem many times with newly planted evergreen trees. There are not enough roots to provide winter moisture and the tree ends up with freezer burn. You should be ok though. It looks like you have plenty of mulch around the root system. There is nothing more that you can do. Good Luck! Looking forward to the update next spring.

Originally Posted by elin
Good stuf, I think he is onto something here. posts like this should be our goal.

It would be good if you could note the electricity charge on the device- maybe connect it to an amperage meter-hour or something and see how much it uses until spring. IT would also make you sure that the device is fail-proof.
If properly mulched and covered i guess even taller trees could be covered with one wire as the heat dissipated upwards.

Originally Posted by TorontoJoe


I actually did a rough calculation. Assuming the temperatures remained below freezing for a full month. My going average electricity rate here is about $0.12 per kilowatt hour. 

Therefore:

30 (watts) X 730 (hours in month) ÷ 1000 (KwH) X .12 (Cents per KwH)

= $2.63 per month. Or just under $0.09 cents per day.

So worst case it's about $10 per year per tree if it ran for 4 months straight.

Originally Posted by ohjustaguy


You should watch some youtube videos on "climate battery" . I think you can do it easily without heat/electricity (except for fan pushing air through battery) if you are going to insulate the soil 6 feet deep. 

This greenhouse consult company has some good info as well:

http://www.ceresgs.com/

Originally Posted by TorontoJoe

OK. Last year I wrapped my in-ground figs like this and despite the mild winter we had, this tree died back to the ground. As you can imagine this had been keeping me awake at night.

   

A few days ago an idea came to me that was inspired (I think) by Johnparav and his glorious Figloo. Also I read somewhere where people do something similar with palm trees in cold weather.

I went to the local Home Depot and picked up one of these:

 

Only 30 watts when it's on

 


Built in thermostat that switches on at 0 C (32F).

 

I unwrapped it and luckily I did. It had been pushed way off to one side against the house wrap I was using to cover it.

 

 
 

A few layers of burlap so it can’t get too warm and around the tree the cable goes.

 

Follow up with a few layers of fiberglass pink and some stakes to keep the tarp from squishing the insulation

  

Finished with tarps and some mulch at the base and topped with a stylish hat.

 

I’ll follow up on this post in the spring for the big reveal. Fingers crossed it’ll be ready to go with no die-back, and that it's not a roasted fig tree…..

I left the others just covered as usual with house wrap and leaves over burlap.....We'll see how they do this winter.