Quote:
Originally Posted by bower
For night covering only, I would get the cheapest and heaviest row cover available. Our Dollar Stores regularly carry the stuff I described. Not useful outdoors but fine in the greenhouse. The nominal value of a 2 oz Agribon ("50") is something like 10 degrees of protection iirc. Just put the cover on before temperatures drop to a critical point after sunset, they'll hold the warmth nicely.
I have used the painter drop sheets as well. And I've combined plastic drop sheet with row cover - this didn't work well for me. Condensation on the plastic, then the fabric touching it gets wet.
Cole, I'm surprised you've never tried the ag fabrics. They are not only for use on the ground, and the professional grade fabrics can have higher thermicity than poly. The Agryl site is pretty cool, check out the 'micro tunnels' for tomatoes. 
http://www.agrylnovagryl.com/applica...o-tunnels.html |
Good point. Introducing the plastic would/could easily encourage humidity. Which at those potential temps could be dangerous.
Im now really thinking that the covers would be the way to go on seedlings that could tolerate cooler temps. Other seedlings though will have to have some kind of heat. Thats ok, as I can reduce the size of bench area that will be heated.
Interesting link.