unheated greenhouse questions

[Dirttiller25]

I built a small 6'x8' lean to greenhouse off the side of my storage building late last summer. It is currently unheated because the weather hasn't been clear long enough for me to finish building and installing the exterior wood heater I'm building for it. I have tomato and bell pepper seedlings I started in early february that are now a few inches high and ready to be potted up into individual cups. My question is what is the lowest night time temperature they can with stand and be ok? I'm currently taking them out to the GH and back in each evening since they are still in starter trays but they really need to be potted up in bigger individual cups. My greenhouse is covered with the wavy clear panels from the home improvement store and has roofing tin along the bottom.

 

[digitS']

My first home greenhouse was probably very much like yours, Dirttiller25. It was fairly conventionally framed, built against my garage, and had used windows in the walls and fiberglass panels for a roof.

The first winter, I put the house plants in it, made some big plans, and turned on an electric heater. The door froze shut. I could do no more than stand outside and look in for most of January. I didn't try heating it through the winter after that.

I'm not sure about temperatures. After a move, I have a different greenhouse now. I'll turn a natural gas furnace on in there soon, to maintain 60°f, overnight. Peppers would like it warmer but do okay.

Every spring, the tomatoes and other plants come out of that greenhouse and are hardened off. At some point, they don't go back into the heat. They are left overnight in a hoop house, unheated.

I did that once with young tomatoes and there was a little frost on the neighbor's roof by morning. Plastic film doesn't hold much heat. I had a thermometer that read 37° right beside some of the plants that died.

Not many plants actually died but many lost leaves. So, somewhere between 60° and 37° is about all tomatoes raised in those conditions can take without injury.

Steve
who knows very well how old and tiring it gets, carrying around flats of plant starts in the springtime ...

 

[Dirttiller25]

I live in upstate SC (Oconee county) the coldest its supposed to get at night within the next 10 days based on the forecast is 42°.

 

[majorcatfish]

I live in upstate SC (Oconee county) the coldest its supposed to get at night within the next 10 days based on the forecast is 42°.

heck your just a county mile south of me....

 

[Dirttiller25]

 

[majorcatfish]

a little personal heater works great on those cool southern nights..

 

[Dirttiller25]

My dad actually gave me his personal propane heater to use today, the kind that goes on the little propane cylinders, but I'm going to try avoiding using it as much as possible to cut costs.

All of the plants will be spending the night out in it tonight as its supposed to be in the low 50s. The tomatoes are permanently out there because they needed potted up bad so I went ahead and did it. It's going to have power in it since it has an exhaust fan so if need be I could always plug in one of the red brooder lights I use for chicks to help keep up the temp.

 

[catjac1975]

Probably just a bit over freezing. But you will stunt them especially the peppers in such cold temps.

 

[valley ranch]

That looks pretty good. I don't think I'd use a propane heater. plants like C02 but not high levels. You might get away by tenting your plants with a single incandescent bulb inside the plastic tent. How many seedlings are you talking about?

Richard

 

[majorcatfish]

You can pick one up at Wally World for 19.00