[Cguitar]

You could build the greenhouse/root cellar with heating/cooling and air movement in mind. Just like any greenhouse during winter, supplemental heating may be needed. If I had such a structure I would store the figs during colder months down in the root cellar and most likely in a climate like Dave's would rarely if ever have to heat to get figs above 25F during their dormancy. 6-8 feet in ground with an insulated roof (greenhouse floor separating them). If the entire structure was well insulated the root cellar would provide more than adequate temperatures for dormant fig trees to survive. In the hot summer Dave could exhaust the hot air inside the greenhouse to the outside. This would then pull some cooler air into the greenhouse from the cooler root cellar.

[FigTreeJunkie]

I think the two would actually work against each other. For the greenhouse, you want to try to raise the temperature on the ground beneath whereas a root cellar targets keeping the temperature low (40F) to preserve food.

[davej]

Yeah, regrettably I would have that issue and figuring out how to obtain the necessary permits would be a headache.
EDIT-- Oh, I just realized that up to a 10ft x 12ft "shed" does not require a permit here.

[Cguitar]

Dave a root cellar with a ground level greenhouse would be ideal if you can build into a hill and your area allows such a structure without too much hassle.

[davej]

I really wonder if I want to insulate and improve my attached garage or dig a root cellar. I have been using the garage but it is certainly not ideal when we have warm winter days or extremely cold nights. Maybe the most fantasical creation would be a root cellar with an upstairs greenhouse? I do have a hill so I could build into the side of the hill.

[FigTreeJunkie]

As another data point. a couple of days ago, the temperature dropped to a low of 7F. Again, in the greenhouse, the temperature low was 25F under the windows, so it was warmer further back.
The barrels of water (thermal mass) has been effective. Other years, the temperature would drop into the teens in the greenhouse.

[FigTreeJunkie]

that's good to know. The outdoor temp had a low of 8F this morning, but the greenhouse only went down to 25F under the window.
The high was 54F yesterday. I can't tell if the heat gained by the windows during the day is greater than the heat lost at night. From your numbers, it may be close. I am closer to the ocean than you are which may account for the few degrees warmer temperatures.

[Vladimir]

My basement fig room has been between 47 and 50F for the last 6 days. Hope it stays below 50F for a while. I plan to just keep an eye on the temps and will take action when temps stay above 50F.

[ginamcd]

Sounds like your set up is doing the job! My fig room was down to 24F when I last checked yesterday evening, and this morning it was 29F so I know the heater kicked on at some point. Tonight it's holding steady at 27.6F (it's currently 10F outside) so it may not get cold enough for the heater to run again (on at 20/off at 30).

[FigTreeJunkie]

Low temp of 8F last night and my greenhouse only went down to 26F measured under the window. Probably 32F near the water barrels.

[Figs4All]

Hi Vladimir, if you can run electricity to your shed you might try a fig box similar to what I made for my basement. I had the opposite need you have, which is to keep my figs above 70 deg F, but it can work for your situation too, to keep your figs around 45-50 deg F (if it is colder outside your shed) if you place a heater in the fig box and control it with a thermostat. You can custom shape your fig box to almost any fig plant size.

https://www.ourfigs.com/forum/figs-h...ent#post690844

[ginamcd]

The heater in my insulated "room" in the shed has briefly run once from what I can tell. So far this winter seems mild in comparison to what we typically see for low temps by this time. However, these next two nights will likely have both our heaters kicking on...

[FigTreeJunkie]

As a FYI, my northern greenhouse has 2 double pane storm doors as windows and then is plywood around the rest with 2" foam covering (most of) the plywood. I also have about 180 gallons of water as a thermal mass.

The past couple of weeks have had a number of days at about 15F low. The greenhouse has a thermometer below the windows (so it's the coldest part of the greenhouse) the has stayed above 28F. I assume this means the temperature in the greenhouse is starting at a minimum of about freezing.

The space heater (turns on at 20F) has yet to turn on this winter.

[ginamcd]

I recall reading in the past that a stretch of temps at or above 55F are needed to break dormancy. If you can maintain 50F, you should be okay. The trick will be maintaining it when things warm up in the spring.

[nycfig]

Lol... It certainly is a ton of work but necessary to ensure survival. We've lost an entire collection and I wouldn't let that happen again.

[TorontoJoe]

You’re going to need to build a cold room or find somewhere appropriate off site

[Vladimir]

I do not have space in yard for boxes but I do have a shed. I was thinking of building an insulated space in it the way Gina did but decided against it because of cost.

[TorontoJoe]

Vlad- Do you have space in the yard to build boxes?

[TorontoJoe]

I would not insulate the floor. The natural siphon should bring plenty of cool air into the room.

[FigTreeJunkie]

The temp at about 8ft down is 50. I assume the top few feet is frozen now.

You can always try the approach TorontoJoe suggested with an insulated room and see what happens if you shut the vents, insulate the floor, e.t.c.

[TorontoJoe]

Good idea. It’s a pain to do from my phone. Will start a thread with this in frequent topics tonight

[VicD NJ7A]

Just thinking about that process makes my stomach churn… I know the terrain up there… I think I had mentioned once that I spent my summers in Delancy with day trips to Oneonta… It’s hard enough to navigate those roads (with a regular car) in the summer months let alone the fall/winter months hauling a trailer. I give you a lot of credit for that..

[Vladimir]

Thank you for your suggestion but I still need to bring the temps to below 50F. Wouldn't I?

[Vladimir]

The problem with leveraging ground temp is that I have been doing that and the temps have been at about 50 F, lowest temp being 49 F. I am concerned that they will wake up too early at 50 F.

[Mr.Figs]

Plese sticky this in the FAQs, Joe.