I have a large, wooden, unheated greenhouse. I pin bubble wrap along the northern side but bottom half only as I don't want to create too much condensation. I just lay loose fleece on the plants if it's going to be especially cold. If it's going to be very cold I light a big "pillar candle" and stand it in a tin, on the floor, in the middle of the greenhouse ( cheap and effective). Don't forget, open the door when / if it's mild as condensation can be a big problem.
That reminds me- If you turn a large terracotta pot upside down you can light a tea light beneath. When it goes out the pottery still radiates heat, just like a storage radiator. Knowing how draughty my greenhouse is I dont need to ventilate, but yes take that into consideration.
Also filling several, preferably painted black, plastic bottles with water & placing around the greenhouse/coldframe. The water may freeze if very cold, but it acts as a 'heat exchanger' apparently & keeps the inside temperature more even. Am no engineer but do still do this. J.
I like the ideas for plastic bottles and upturned terracotta pots, plumstrudle. My greenhouse dosen't have an electric supply, and have shied away from oil heaters as I don't want to bother with an oil supply, so will try this. I wondered about a small solar panel; have not seen one marketed for greenhouses, though I did get a solar-powered water pump which worked well for 2 years then packed in. Though I guess if you don't insulate, these might all be a bit futile. Perhaps a double-glazed greenhouse............
Ginny May, I have seen 2 systems for solar panels for greenhouses, 1 at Hampton Court flower show last year and one (v. expensive) www.solarpvgreenhouse.com
Artjak it's my first year with a greenhouse as well, I have found all this info sooo helpful, Am now going to construct a warm area within greenhouse based on this info.
Ok - Put up mini greenhouse (found out its called a pot greenhouse) inside big greenhouse and put more tender plants in it raised up on some veg trays bought earlier. Have told OH he has to have soup tomorrow for lunch so that I have a tin to put a candle in. Have candles -they are chunky and were in the little bit of sun we had in the summer and melted and are misshapen so will use those for heat source only on coldest of days(nights). Feel well satisfied with that - now will just have to wait and see if it works
I think Jo you are really a mine of good sound economical gardening advice Pat on the back
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I have a large, wooden, unheated greenhouse. I pin bubble wrap along the northern side but bottom half only as I don't want to create too much condensation. I just lay loose fleece on the plants if it's going to be especially cold. If it's going to be very cold I light a big "pillar candle" and stand it in a tin, on the floor, in the middle of the greenhouse ( cheap and effective). Don't forget, open the door when / if it's mild as condensation can be a big problem.
just bought 30mts roll of bubble wrap cost 5.99. cheaper than buying plants next year.
Thanks for the advice re insulating greenhouse with bubble wrap. Will def have a go and see what happens.
That reminds me- If you turn a large terracotta pot upside down you can light a tea light beneath. When it goes out the pottery still radiates heat, just like a storage radiator. Knowing how draughty my greenhouse is I dont need to ventilate, but yes take that into consideration.
Also filling several, preferably painted black, plastic bottles with water & placing around the greenhouse/coldframe. The water may freeze if very cold, but it acts as a 'heat exchanger' apparently & keeps the inside temperature more even. Am no engineer
but do still do this. J.
Thank you everyone. So many hints. i hope other gardeners find the hints useful as well
I like the ideas for plastic bottles and upturned terracotta pots, plumstrudle. My greenhouse dosen't have an electric supply, and have shied away from oil heaters as I don't want to bother with an oil supply, so will try this. I wondered about a small solar panel; have not seen one marketed for greenhouses, though I did get a solar-powered water pump which worked well for 2 years then packed in. Though I guess if you don't insulate, these might all be a bit futile. Perhaps a double-glazed greenhouse............
Ginny May, I have seen 2 systems for solar panels for greenhouses, 1 at Hampton Court flower show last year and one (v. expensive) www.solarpvgreenhouse.com
Thanks, artjak, will look into them and maybe drop strong hints to Father Christmas!
Artjak it's my first year with a greenhouse as well, I have found all this info sooo helpful, Am now going to construct a warm area within greenhouse based on this info.
Let's hope it works
Bjay
Ok - Put up mini greenhouse (found out its called a pot greenhouse) inside big greenhouse and put more tender plants in it raised up on some veg trays bought earlier. Have told OH he has to have soup tomorrow for lunch so that I have a tin to put a candle in. Have candles -they are chunky and were in the little bit of sun we had in the summer and melted and are misshapen so will use those for heat source only on coldest of days(nights). Feel well satisfied with that - now will just have to wait and see if it works
I think Jo you are really a mine of good sound economical gardening advice Pat on the back