The cost of heating a greenhouse in winter can sometimes be greater than the savings and advantages of using one.
On this page some cheap ways to heat-up a greenhouse without using electricity;
Mini plastic greenhouse. If you can't be bothered to bubble wrap your greenhouse. However, still want to grow plants in winter, try placing a cheap mini plastic greenhouses inside the glass greenhouse.
The main loss of heat from greenhouses is from draughts and through the structure so these five simple maintenance and insulation tips will help keep your greenhouse warm.
Greenhouse Paraffin heater for winter.
Paraffin heaters are the simplest way to heat a greenhouse up to about a maximum length of 8ft in winter.
If heating demand is not too high through winter and outside temperature does not fall below6C and the required greenhouse temperature is not more than +5C, this paraffin heater will keep your greenhouse free of frost.
If you use a greenhouse heater you can help keep greenhouse heating costs down. And still grow plants through late Autumn and winter months by adding a layer of bubble wrap to insulate your greenhouse. See the amazon advert.
I found this Idea for a small greenhouse heater using a nightlight, a saucer and a terra-cotta pot on a forum. Usually a night light lasts eight hours so I’m going to experiment with these in saucers beneath a metal bucket and on a saucer in an old watering can.