hoop houses

Does anyone know how cold it can be outside before a hoop house covered with 6 ml plastic will get below freezing if I don't have heat in the hoop house?

Louise,

If the hoop-house isn't heated, and only has a single layer of plastic (with no dead air for insulation) then it will get cold pretty quick. The ground will heat up some during the day, and return that heat overnight. After a couple of cloudy days, though, the hoop house will be as cold as outside. You can improve that by adding more "thermal mass". Many people use barrels of water, which heat in the sun, then hold heat longer as the air cools. If you really want to keep an area warmer for an extended time, then you need insulation and extra heat.

David

Well said David. I can add the temp in my hoop house at night is about 1 degree warmer than outside. Thats not enough in most cases to do any good.

What I do do is cover my plants with insulating blankets I got at the nursery or buckets or both. works here Ernie

Thanks for your input, that answered what I needed to know