Greenhouse Hothouse

Well, I verified that the greenhouse can get a bit too warm when the sun is shining. Even though the outside temperature was only 37 F at 2 pm yesterday, the surface soil temperature was 95-125 F! I promptly cut a slit in either end of the green house to allow some air to flow through. When I checked again at 7 pm, the temperature was down to about 50 F with an outside temp of 40 F. I pinned the opening closed and when I checked this morning at 8 am, the soil temperature was 40 F with an outside temperature of 30 F and an overnight low of 28 F.

I started two microblock trays of veggies and flowers Sunday evening. That is 180 blocks per tray, about 360 seeds. I am trying to start zinnia, delphinium and alyssum from seed. I also started several varieties of tomatoes and peppers, celery, basil, tatsoi, choi, mizuna, and lettuce. Everything has bottom heat compliments of a 6' strand of incandescent rope light. That appears to be sufficient to raise the soil temperature to 72 F.

I decided that having the greenhouse, I will sprout the peas in a jar and then just plant them directly. I will also direct seed lettuce, carrots, beets, radish and spinach.

Update: the following day, I checked the temperature inside at noon and found that it was back up to 125 F on the garden frames. I cut the plastic all the way down and opened it wider to allow air to flow freely through the greenhouse.