Alternative ways to heat a greenhouse
Comments(15)
Photo: Shed and stone dog
The windowsills in the cottage and the greenhouse are already packed with seedlings. I was determined to get everything off to an early start this year. The little electric propagator is working 24/7 and seeds are germinating really fast.
Even though the greenhouse is lined with a thick layer of bubble wrap it needs a bit of extra heat to keep the temperature above freezing on really frosty nights. Do you remember that I bought an ancient Eltex greenhouse heater at the church fete last year? When the frosts hit I tried to light it with no success so turned to my paraffin heater that I bought when we built the greenhouse. We have a maximum minimum thermometer in the greenhouse and I noticed that over night the little paraffin heater often just didn’t have enough welly to keep the temperature above zero.
The option was to either buy another heater or to get the Eltex one up and running. Determination and spray oil is a perfect combination. I doused all the moving parts with it and let the oil permeate for a few minutes. Then with a bit of a creaky cronky start everything was working well. This heater is great as it has a large surface area which heats up quickly. A much better design than my old heater which just heats the chimneys and the little metal roof on top. Even running on just two wicks, rather than four, the vintage Eltex heater is keeping the greenhouse warm and snug and I’m delighted with it.
However paraffin can be quite pricey and during the really cold weather in January most of the Newmarket shops ran out of supplies. One of the entries for our recent gardening competition was from Kate (UK). She had an ingenious suggestion for a small greenhouse heater using a nightlight, a saucer and a terracotta pot. 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. They would be a cheaper alternative to paraffin if they work. In fact I probably could adapt the Eltex heater to run on night lights too.
Watch this space.
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Tenacity, determination and a little bit of ‘Heath Robinson’ goes a long way! xx
Black painted water containers to absorb heat during the day and a brick heated with your stove during the day are other possible solutions but not for the really cold days obviously
Congrats on the Eltex! Can you tell me what kind of night light you are referring to? Night lights in the U.S. have small bulbs and plug in and make no heat. Is this a kind of candle? Sounds interesting!
great ideas, squirreled away for when I have a garden again
Hi Fiona
my parrafin greenhouse heater uses 4lts a week which costs £5.55p, I however tried mine using Diesel (initially from the car) and found that after a bit of wick adjusting,(too big a flame tends to smoke) it ran perfectly well!
Diesel here is £1.10 per ltr, so i`m saving £1.15 per week. Maybe you could try yours on either Diesel or heating oil?
Yeah- I didn’t understand that night light reference. Here in the States a night light is a little 15w electric bulb in a tiny socket plugged into the hall outlet or the bathroom outlet. They don’t put put out any heat at all- well, not much. Even the 40w bulbs don’t heat very much.
Could you explain Kate’s night light?
Hello Everyone
A night light is a small flat candle in a soft tin casing. Sometimes called a tea light. The sort of round flat candle that you might put in a votive candle.
When I was a small child I often had one beside the bed, in a saucer of water, at night.
I remember reading somewhere (Seymour maybe) that if you can keep the seedlings safe from them (questionable) that putting your chickens in the greenhouse at night will keep things pretty warms. Just from the body heat the generate I guess. I’ve never tried it though since I have not had a greenhouse (yet!)
If you put nightlights under pots won’t they go out? Intrigued as I’m about to wash down our greenhouse and whack up the oil-filled radiator in preparation for my own seed germinating. Only just starting. Snowing here. Did you start your seeds in the last lot of snow? Well done if you did!
We will be planting seeds today as this year i want lots of differnt herbs going i have 6 growing now and there in the window, get some church candles as they last for ever.
Hi Joey
I really didn’t want to shell out for another heater and the old one is so much better now it’s working.
Hi Joanna
Great ideas, thanks.
Hi Saundra
I hope you got my reply! They are a sort of flat candle.
Hi S.o.L
I love the swapping of ideas!
Hi Steve
I’m definitely going to give the diesel a go. Thanks.
Hi Paula
I hope that you got my reply. They’re a kind of flat candle.
Hi Gillian
What a great idea! I Think my flock would eat everything in a matter of minutes…
Hi Seahorse
They need to be pots with a hole in the bottom for drainage.
Hi Mutley
We are growing loads of herbs too. Thanks for the tip about the church candles.
Why not say its a tea light instead of some other silly name. Dont be such a skinflint and buy the parafin.
I find that if I buy something labelled as a tea-light, it has a burning time of only 2 – 3 hours. Not much use for overnight, when the winter night is well over 12 hours long. Nightlights, though, are a different matter and as already mentioned, have a burn time of around 8 hours.
I use a nightlight under a clay pot in my 4-tier growhouse, which seems to have been frost-free this winter – albeit with the help of a couple of bottles filled with hot water on the worst of the cold nights.
Hi Cyril
I don’t think I’m a skin flint! Just don’t want to waste money.
Hi Lizie
Yes I find tea-lights have a very short burn time.
Really interested to hear that you kept your 4 tier greenhouse frost free using the nightlight/claypot idea. The bottles of hot water must make a difference too.
Hi Fiona,
You could also try making one of these self-heating greenhouses..
http://www.postcarbon.org/article/88391-solar-greenhouses-chinese-style