frost above freezing

[brian]

Weather forecast for last night and tonight is 37F.   I noticed frost on my windshield this morning but NOAA says it never got below 36F in my area.  Is frost above 32F damaging to frost-sensitive plants?  I know most citrus can handle down to ~30F but it still makes me uncomfortable.

[mrtexas]

Weather forecast for last night and tonight is 37F.   I noticed frost on my windshield this morning but NOAA says it never got below 36F in my area.  Is frost above 32F damaging to frost-sensitive plants?  I know most citrus can handle down to ~30F but it still makes me uncomfortable.

Your leaves will be at 32F even though the air temperature is 37F. They cool off from radiative heat transfer.
The leaves are radiating heat to outer space which is very cold!

[brian]

Thanks.  I suspected this was the case.  Hope they are doing alright, I know some had tender new growth and I have a mango outside also.