Heat transfer in a heated cold frame
I am in zone 5 and want to start seeds in a cold frame that I am going to build and put a heat wire in the bed. I want to use plastic 6-packs for ease of transplanting. What do I need to do to ensure that I get good heat transfer from the heat wires, through the plastic pots, and finally to the seeds? I don't want to fail after building this new planting ability. Thanks, Doug.
Make sure you check the seed packets for information on the temperatures needed for germination. Not every seed needs the same temperature.
Most germination heat mats have a reostat that can be changed to the proper temperature.
Do you have a way to control your heat wires you mention?
Since I'm not clear on the type of 'heat wire' you mention, it is difficult to make a recommendation.
When using a seed heating mat system the pots or germination trays sit direction on the mat.
Make sure you also have ventilation in your cold frame.