Nancy,

I think I would be more worried about overheating. My starts are in a glass greenhouse facing South. My issue is it ramps up to 100 degrees inside on a 60 degree day, then drops to outside temps at night. If your house is small enough you could raise and lower shade cloth as needed.

Eric

Eric,

You're lucky. One day last week it was 45 and cloudy when I left for work and was suppose to remain partly cloudy and cool all day. I didn't open the door because I didn't want to have to keep the heat-er on. The weatherman got it all wrong - turned really sunny and the temps got into the high 50s. By the time I got home at 3:00 it was 125 inside.

Mike

Eric
Never trust a weatherman. Here's a link to the most accurate weather forcast around. Just plug in your city. You can get 15 day forcasts or hour by hour.

I unplug my heater and crack a vent if I'm going to be away for the day. As long as the plants don't freeze, it's better than frying

Here is a link that might be useful: Best weather forcast