Shocking revelation, the sun heats up the soil!!

Soil temperature on sunny days.

Did you know that the sun will heat up the soil.... Yeah no kidding.
While this is common sense, this research is giving us a more detailed look into conditions in the soil and is showing us just how much of a difference there is.  As would be expected, the vegetable plot in the sun heats up more compared to the perennial plot in the shade.  Additionally, deeper into the soil profile will have cooler and more moderated temperatures.  Below is a snapshot of data from early June when it was warm and sunny- with some details and insights.

The graph above was pulled off of ZentraCloud and shows the soil temperature over a couple of days.  This shows that as expected, the deeper you move into the soil, the cooler and more even the temperatures.  

Perennial area in shade with higher humidity

• In the shade temps are cooler and don't fluctuate as much
• Between 4 and 8 inches, there is a daily fluctuation of about 6-8 degrees.  Specifically from 68 to 73 degrees.  
• Temps peak between 7pm and 10pm
• It take about 10 hours to heat up
• There is only a couple of degrees difference between 4 and 8 inches
• The night temperatures stay warmer than the Vegetable bed  
• Higher relative humidity
• Closer to creek
• More canopy
• More tree cover

• The sunny area in the vegetable bed has more drastic changes



Vegetable bed out in open with lower humidity at night

• At 4" the soil temp jumps from 66 to 84 degrees
• It takes only 4 hours to reach high temps
• Temps peak between 2pm and 3pm
• At peak there is a 10 degree difference between 4 and 8".  73 vs 84 degrees.
• Gets cooler than the perennial plot likely due to humidity
• More heat is lost at night
• Little plant canopy
• Out in the open  

We have data on cooler days and can also see the 4" readings drop occasionally when it rains.  More on that and other measurements later.

Kevin