Selecting a Greenhouse

[quote=butterflywoman]oh yes, greenhouses are not turnkey…they require attention just like any garden, or things of value.
it really depends on where you live with what you can do.
my greenhouses are unheated by out side sources…strickly solar or free
you can, however, heat a greenhouse and grow way more selection of plants…but cost evectiveness goes out the window as the temp needed increases.
i can simulate in michigan zone 5 , growing conditions in atlanta zone 8 with an unheated greenhouse.
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What are your tricks? I’m in Michigan zone 5 too.  Entering our 2nd season with a gable greenhouse.  Last year had to supplement with space heat. Not growing anything this winter, new baby keeping us busy enough. So may be a good opportunity to experiment with non-power heat. Do you use foil or bubble wrap?