Minnesota Apples Wiped Out Tonight?
In the picture are a couple apple trees with beautiful blossoms. Given the forecast you have to wonder how they will look about mid-morning Tuesday. The National Weather Service has issued a frost advisory for 4:00 Tuesday morning. The forecast is for a low temperature of 33 degrees. You have to hope that maybe the clouds hang around until after sunrise tomorrow morning which can trap warmer air near ground level, or maybe the temperature stays a little warmer the in the forecast.
I have had David Bedford PhD. who is the apple breeder at the University of Minnesota Landscape Arboretum as my guest on KDHL's Am Minnesota Program and we have talked about cold temperatures when the apple trees are blossoming. If the blossoms are killed by frost the tree will not produce apples this year. I remember a few years ago we saw a late spring frost and greatly reduced the apple crop.
Bedford said there are many factors in addition to actual temperature that can damage the apple blossoms such as humidity, wind and many more. Bedford said he has seen actual temperatures as low as 28 degrees and the apple tree was not damaged. Then another night maybe the actual was 33 degrees and they see that the tree had some frost damage to the blossoms.
You will not know for sure until later on Tuesday morning if the apple trees were damaged by the cold temperatures.