Have a lean-to greenhouse! They have the advantage of getting some heat from your house in winter, either heat that would be lost, or if it is very cold, you could open windows into the greenhouse to let your house heating system heat it. Much simpler and less dangerous than any greenhouse heater. On warm sunny winter days, the greenhouse will actually add heat to your house. And Humidity. And Oxygen.
The Warmax Paraffin Anti frost Heater needs no electricity, is simple to operate and economical to run. It will keep a greenhouse up to 2m² frost free and will run for 10 days between filling. http://www.harrodhorticultural.com/warmax-paraffin-antifrost-heater-pid8325.html Warmax Paraffin Antifrost Heater
Keep your greenhouse frost free this winter! These Frosty Greenhouse Heaters from Bio Green are extremely efficient, thermostatically controlled gas heaters for creating the ideal temperature in your greenhouse to grow year round and stop frost damage to plants in winter http://www.harrodhorticultural.com/bio-green-frosty-greenhouse-heaters-pid9170.htmlBio Green Frosty Greenhouse Heaters
Without the proper greenhouse heating system your plants could experience uncomfortable levels of low temperatures that might be harmful to them. Plants require the optimum temperature to stay healthy. Temperatures can vary a lot during the daytime and especially during the night. When investing in a greenhouse heater, a few things have to be taken into consideration. Factors such as cost, type and your unique requirements come into play.