Building a greenhouse can be inexpensive if you use recycled doors or windows. And a small greenhouse is a great way to grow a few vegetables right through the coldest months of the year. Green Houses, Recycled Window, Greenhouses Plans, Building A Greenhouses, Mothers Earth News, Diy Greenhouses Storms Doors, Old Window, Window And Doors, Small Greenhouses
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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.