Frost Advisiry Monday Morning
The National Weather Service has issued a Frost Advisory for Monday morning from 1:00 am to 8:00 am for Southern Minnesota. Temperatures are expected to drop in our area to 30 to 35 degrees by sunrise Monday morning. Sensitive plants may be killed unless they are covered or brought inside. So, if you have already planted flowers cover them with towels or blankets before you go to bed tonight.
A frost Monday morning would have little impact on our crops. The corn that has emerged would shoot new leaves from the growing point that is still underground very quickly. A lot of soybeans have been planted but very few have emerged yet. Even if soybeans have emerged they have a "waxy coating" on the leaves which means it takes temperatures down to 28 or 29 degrees before they are killed.
I am concerned about one crop in our area though, apples! At this time of year the apple trees develop flowers and those flowers turn into apples. The apple tree flowers are very sensitive and can be damaged by temperatures at 32 degrees or lower. A frost will not really damage the apple tree. However, a frost could kill the flowers as has happened in the past.