Today I harvested my first baby lettuce from some of the lettuce plants that I'd started inside the house and planted in the cold-frame. It wasn't much, but as I ate it I felt gardening season had begun.
The lettuce, broccoli raab, and baby spinach seeds that I planted in the cold-frame last week have already sprouted and will soon need thinning. From my temperature readings, I have noticed that the cold-frame nightly low is staying about 9 or 10 degrees warmer than the low temperature outside of it. This would mean the the low temperature approximates late April temperatures instead of late March temperatures. I think if I'd finished the cold-frame sooner I could have started planting lettuce sooner. That will be an experiment for next year.