A greenhouse offers superior protection for your crops than leaving them outdoors, especially during the dead of winter. Still, it may be too cold for some things you would like to flourish. However, there are great ways to maximize the heat in a greenhouse – without investing in a purpose-built heating unit! (I’m currently exploring the idea of Bitcoin heaters for my greenhouse. It’s insane, but Bitcoin heaters may help keep your small greenhouse warm while reducing your electric bill. We live in crazy times!)