I generally start plants with bottom heat in trays for a few days.
After emerging I take off the plastic top and place out in a bright spot
for a few days bring in at night. Than I move the culled survivors to
a cold where they reside until the night is above 50 F. Then outside
still in their trays for a few days, Then into the garden.

Any improvements would you suggest?


Found below link but it is chemical in path forward.

Bill who stores old milk bottles in cold from to moderate temperature.
Heat sink in a way.

http://home.insightbb.com/~g.mager/Growlab/Gen-seed-start.html

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Garden in shade zone 5 S Jersey USA