wendy7 wrote:
Thanks for this Tom, interesting reading. The ground is 5 degrees warmer if watered???


It's not really warmer. With outdoor gardening (in the ground, not pots)
the soil is still pretty warm when those first fall frosts occur. Wet
soil does a much better job at conducting some of that warmth to the
surface where it can make a few degrees difference to the plants growing
there.
The article was about protecting a garden from early frosts and quite a
bit of it doesn't apply to orchids in a greenhouse.

Steve