On Sat, 28 Mar 2009 15:33:28 -0500, "Denis Mitchel"
wrote:

Does the temperature have to be at or below freezing for frost to form on
plants?

Thanks



For moisture or water to freeze the temperature must be no higher than
32 degrees F, and then additional heat must be removed for the water
to phase-change to a crystal lattice structure (ice). No ice will
form above 32 degrees, but certainly there can be supercooled (or
contaminated) liquid water below 32 degrees, which is added frost
protection for the plant.