At What Temperature Is Frost?

Q: Can frost occur at temperatures above 32°F? A1: No, frost is defined as a layer of ice that forms on surfaces that are at or below 32°F. Sometimes frost can occur on your lawn overnight, even though your thermometer may never have dropped to the freezing mark.

Can you get frost at 40 degrees?

A rule of thumb: If the dew point is above 45 degrees at sunset then you are probably OK. Below 40 degrees you will probably see a frost if the other conditions are good.

When should I cover my plants for frost?

Before you cover the plants in late afternoon or early evening, water your plants lightly. Apply covers in early evening as winds die down, and remove the coverings when temperatures rise the next day (mid-morning) so that plants can get full exposure to the warming sunlight.