Note to readers, attached is the complete final report for FNE93-029.
Heating the soil in an unheated tunnel made no difference in this experiment, but I believe this is due to the solar plant’s unreliability. It was eleven days after transplanting, that afternoon soil temperatures were consistently 80 degrees in the heated row. Soon afterwards, the temperature in the unheated row would approach this. These temperatures were also much closer by morning. Had the water been heated with propane so soil temperatures were maintained at 80 degrees there might have been a notable difference in early growth between the unheated and heated beds and as a result a difference in early yields. Cool and cloudy early May weather, along with a warm late May also reduced the profitability of tunnel crops.