-2°f temperatures killed the carrots inside both greenhouses, they had no heat and no thermostat then.
Now I have a 120 volt bi-metal thermostat $15 on ebay and a 60 watt incandescent light bulb for heat. It is 34°f outside today and 60°f inside both greenhouses. What ever the temperature is outside the light bulb keeps the temperature inside the greenhouse 26°f warmer. When the sun warms the green house above 65°f the light bulb turns off.
The 2 green houses are about 20 feet apart. We had some generic yellow grocery store potatoes in the pantry that were growing eyes. Wife pealed the potatoes to use them up before they go bad. After carrots died I had no clue what to plant in the 2 greenhouses so I tossed potato peelings with eyes in the west greenhouse. Soon potato plants started to grow, plants are now about 5" tall. 2 days ago we had full sun, I notice temperature inside greenhouse was 140°f, no problem for potato plants so far. I vented the greenhouse to let out some of the heat.
East greenhouse has nothing growing in it. I can't think of anything to plant at the moment? Maybe tomato seed and pepper seeds about March 1st.
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