Answer: The soil should be showing a warming trend. If you use your probe to measure it at seed planting and initial rooting depth, it will not be right on the surface so it will fluctuate a bit less. Most seeds germinate at a range of temperatures, so it does not have to be that precise. In the early spring you are more concerned with it having reached a minimum. Later on you will more worried about it being too hot.
I would suggest you check with your county extension and state department of agriculture for information about any permits you might need. They will have the most up to date information for your state and any local requirements.
Good luck with your market garden!
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