Here is a quick update.
It snowed last night. The temperature during harvest was 30F. The carrots are in the unfrozen bed. I remove the plastic and dig the carrots up.
I try to eye-ball-it and harvest enough carrots to do 4 jars.
A photo of finished pickled carrot jars. I also have 4 more cooling down in the pressure canner. I do 4 jar batches.
The cold ground keeps the carrots crisp and fresh until they are processed!