Greenhouses are poorly insulated structures, and heat loss through the covering on cold, clear, windy nights can be considerable. Heat can be supplied using electricity (can be expensive), natural gas or propane, fuel oil, solar energy (unreliable), or kerosene (emergency use only). You can also connect the greenhouse to your home heating system. Natural gas or propane are probably the most cost-effective ways of heating a hobby greenhouse. If natural gas is available in the home, plumbing into the existing line saves considerable cost over a new meter and gas line. If natural gas is not available, check with the local propane gas company for cost and availability.
