Xmas Light Seedling Heat Mat

[dice]

I had excess seedlings in unheated clear vinyl mini-greenhouses last
spring with a trouble light in the bottom to keep them from freezing at
night where day and night temperatures were below the temperatures
used by commercial growers described in that thread.

The seedlings still inside under flourescent lights were healthier
and faster growing, despite having considerably less light. Both
had the same seedling mix, etc.