I like the looks of that!! Where do you buy the straw bales in Phoenix? Maybe they grow some grains in the valley but I’d think they’d have to ship those in.
Oh they grow lots of grain in the valley. Straw is commonly available. We buy it by the squeeze for about $5 a bale. In our straw bale houses with a couple of strands of C9 christmas lights hooked up to a temperature controller and capped with a double layer of Agribond 50 frost cloth im good down to the low 20’s. Topped with a blanket of some kind instead of the frost cloth im good to the mid teens. Its simple and it works, been using this system for years. It should be very adaptable for you folks that just need to take a few degrees off to save fruit buds or whatever.
I have a temp sensor in one of my container trees in my attached/unheated garage…last night the outdoor temp was -15F while inside the garage it was 2.4F…
Rob (aka franktank) Even though your garage is unheated I’m guessing the ceiling is sheet rocked? I usually am only about 7 degrees warmer in my garage than outside. I think all the heat just goes up thru the ridge vents. Sheet rock or paneling on the ceiling would probably really help me… but then where would I stick all the junk I don’t need? 
Frank,
Right now I got a 2nd leaf Spice Zee, and a brand new potting of Flavor Supreme, King, Queen, and Leah Cot Aprium. After lasts night chill the garage got down to 32F. The coldest its been this year has 29F before I kicked the heater on and brought it up to 39F. What do you as far as container trees? I’m still adding a Weeping Santa Rosa, Sweet Treat, Dapple Supreme, and Nadia this season.
Klondike-
So much junk…so much. The worst thing about owning a home seems to be the accumulation of stuff. Back when i was a renter, I could fit my whole life in a Honda Prelude.
The ceiling is wide open rafters with some junk tossed up there…the walls are insulated. The garage door is also insulated. The wall facing the house is insulated really well…but my guess is there is heat leaking from the door…
I’ll keep tabs on it some more and see how the temp responds…i’ve always thought it wasn’t much warmer then outside, but i guess i was wrong…if the ceiling was insulated it would make a HUGE difference. I know my brother’s garage was easily kept above freezing with minimal amts of heat. That was a well insulated 3 car garage (mine is 2). Insulating is on my list…just need to clean it out. Sheetrock has an R value of around 1 so i’d at least throw some fiberglass batts up there.
You could save your storage by insulating the roof. Either spray on foam or foil covered styrofoam about 3 inches thick. That’s becoming a common way to insulate attics. The cheapest would be blown in cellulose.
The straw bale idea is giving me tons of ideas. I do grow several citrus, some bananas and tons of plumeria. Most all in pots. My citrus and others like desert rose and some succulents go in the greenhouse. I keep it above 55 at all times to avoid any leaf drop. My bananas, mostly basjoo overwinter in the ground here just fine. They do die back all the way. I am growing a Dwarf cavendish that I grow inground and dug up in the fall. My plumeria spend the winters in the front room by a bright window and just sit dormant. I did grow a few in the ground and dug them up in fall. They are doing just fine and will go back in ground in April.
My goal one day is build a greenhouse that I can put my citrus in the ground permanently. During the summer I would remove the greenhouse covering and put back in fall.
mk:
I’ve wintered citrus in my greenhouse 11 yrs in ground and potted. Never have I heated above 39F and never any significant leaf drop. I want nights near 40 for chilling. That’s what they get all winter in CA commercial citrus districts. Works for me and them don’t see why not for you. That way you can grow all the things I do in one greenhouse.
But here’s the kicker I keep days in 50s to low 60s, just like CA. You might need 55 at night for root growth if you let it get 90 on a warm sunny day. At 90 you need active roots to pull out water.
The cold doesn’t hurt fruit eating quality.
Just something to think about if you do build another greenhouse.
FN…
And I just keep buying the MEGA MILLION tickets and hoping that I can have the chance to have you design my greenhouse.
Mike
Thanks Fruit. I keep mine at 55 because they are all in pots so Im trying to keep the roots at or above that temp because it does easily get to 80+ during the winter days. That seems to work for me. Also we just like going out there on cold nights and 55+ feels better that 40 LOL. ours is just 10x12 hoop house so it doesn’t cost a lot to heat. My next one is planned to be at least 10x20 or 24’.