Extreme cold heat alternatives wanted

[kingoceanos]

Hi all, I live in Conroe Texas (8b) and we are going to get hit with the coldest weather since 1989. I usually throw sheets over my citrus with halogen floodlights under and they have always done fine, but they are talking about low's of 9 degrees for my area... So I don't know if my normal winter protection will suffice. Also the halogen bulbs are getting harder to find and more expensive. So I am looking for other heat sources that are easy and inexpensive to use. Normally we see very few freezing days in my area.
Thank you. 

[shot]

Enclose in a sturdy pvc structure covered in plastic and anchored to ground.Then run irrigation 24/7.Put thermometer in that you can read through the plastic like a big dial thermometer.You will be surprised.No low volume irrigation heads!
 When its over it will be just a bad memory,but you will have your citrus for years!

Does not have to be perfect just functional for wind load.University of Fl did trials with open top small structures for citrus replants.You need top closed as (size )of plant and temp,(wind )demand it
Your goal is to create a dead air space and continually fill with moisture and heat

[Jaboticaba45]

I made a wooden frame, then put plastic wrap over it then lit a candle to protect my in ground citrus. Made it through 17...not sure if it would work when it is colder though.

[Tropical Bay Area]

People in zone 8z are being hit by 0-3 degree cold... man that really sucks! Hopefully everything will be fine   

[kingoceanos]

Thank you for the suggestions. I really need a electrical replacement for the halogen floodlights. They are becoming harder to find and more expensive as they are being phased out in favor of the L.E.D. energy efficient bulbs.
Thanks again

[TonyinCC]

Multiple candles or sterno burners(only 2 hour burn time for those) could work in a pinch but kerosene lanterns are ideal IMO because the flame is adjustable, it won't get blown out by wind, or catch things on fire as easily. They also supposedly will go out and won't start a fire if tipped over.
I used Dietz kerosene lanterns to protect citrus when I lived in South Carolina. Keep in mind they need oxygen to continue burning but covering a tree usually will allow enough air leakage for it to continue burning. I might suggest several of the smallest sizes on the ground in a triangle around the tree instead of one larger one depending on space under cover. Got to make sure you don't melt or burn whatever you are using as a cover or cook the tree.
Kerosene lanterns can be used in a greenhouse as well overnight but will fill it with Co2 so allow to vent completely before re-entering or you may die. (even if it is still burning the Co2 level might be toxic)  It is a trick you can use to increase plant growth by enriching the greenhouse with Co2 when not used for cold protection.
 They put out enough heat to heat a can of beans or fry an egg in a small pan albeit slowly like using a low heat setting on a cooktop stove.We improvised a vented cover to make the top flat. They used to make a model that could be used specifically for that purpose that had a flat top attachment. We had a hot meal during an ice storm years ago but it took a couple hours to feed 5 that way. We always took lanterns out to wait for the school bus with the kids in the mornings at the farm and they were great for warming hands a few inches above the top of the lantern.

[Daintree]

We are zone 6 and I have a friend who has PALM trees in his yard!  He wraps Christmas lights (the little ones) all around the trees from bottom to top, drops burlap sugar sacks over them and fills them with leaves.  Instead of burlap, your sheets would probably work fine.  The trick is the gentle warmth right up against the trees, and the insulation of leaves.

Good luck!

Carolyn