Greenhouse Gardening – environmental issues

If you’re using a greenhouse to grow your own fruit and vegetables then pat yourself on the back because you’re reducing the energy needed to transport and store food to the shops, which means you’re benefiting the environment a great deal. If you grow organic, then you’re really doing the world a favour!

However, heating a greenhouse in the winter months can be wasteful because by their nature, greenhouses are poorly insulated and producing the energy used to heat them contributes to climate change. On the other hand, making some changes when setting up and using your greenhouse could eliminate the need for winter heating altogether:

Begin by ensuring you keep your greenhouse panes clean, especially where glass or plastic overlaps as grime and cobwebs dramatically reduce light levels and cut down on the free heating that you gain from sunlight.
Set your greenhouse in a bright spot that gets sun all day and isn’t shaded by trees or walls
A lean-to greenhouse that shares a wall with your house will need less heating
Free-standing greenhouses with the lower part made of brick or timber conserve heat better than all-glass models – if you have all glass, lean old cardboard, straw bales or wooden pallets against the bottom panes to make an air gap that acts as an insulator, trapping heat
Seal gaps around poorly-fitting panes or doors to stop heat escaping – and put up a door curtain for the winter so that heat isn’t lost when the door is opened
Run guttering along the greenhouse and a water butt to collect rainwater for your plants
Consider moving less hardy plants indoors for the winter instead of heating the whole greenhouse for their sake.

Greenhouse gardening strawbale photograph by Swastika Boy, used under a creative commons attribution licence