Terracotta Pots And Tealight Heater

[peanut]

Hello Folks,

I was wondering if any of you have tried the terracotta pots with tealights/candle heater for your greenhouses to keep the frosts off?
I saw it posted somewhere else and have had a bit of a google but I'm not sure if it would work in an 8 x 6 greenhouse.
I think I will give it a try though.
Have any of you done it?

[Nicos]

I’ve not, but I imagine it only raises them temperature by a degree or so?
Might be better with two or three of them maybe used in conjunction with bottles of hot water giving off heat?..plus fleece?

I didn’t have my greenhouse long enough to play around with those ideas.

Let us know how you get on!

[Mark Rand]

Tealights put out about 32W of heat. Tiny in comparison with an electric or paraffin greenhouse heater.

A calculation on stackexchange estimated a temperature rise of 0.2°C in a 2mx2.5m greenhouse from a single tealight...

[Jungle Jane]

Do you have a lot of plants needing protection Peanut? Some people put their blowaway inside the greenhouse for extra warmth,a candle pot heater would heat a smaller area easier than the whole greenhouse.

[mothhawk]

A tealight is only going to burn for 3 to 6 hours, so either you'd have to replace them in the night, or not light them till very late.
probably be as cheap over time to buy a little solar powered camping heater.

[Snoop Puss]

I've got a feeling that rary tried this, but I can't find any of his posts in a search. I'm pretty sure his experiments with them must have proved unsuccessful as he has tried a number of methods to warm his greenhouse. That said, he's a lot further north than you, so you might have more luck. This post from quanglewangle might prove of interest, as he suggests it's not just the warming but also the movement of the air that helps:

https://www.growfruitandveg.co.uk/gr...60#post2523860

[bramble]

I tried a few times mny moons go..I really dont think it made a difference.
I also tried the bottles of hot water with the same result.
Now I only use my greenhouse for over wintering my geraniums and a few other tender plants
I find a few layers of fleece to be about the most effective unless you want to use an electric heater.

[rary]

Hello peanut, as Snoop has said I did try this system out but with poor results, though if you take some of the tips submitted on this post, like creating a smaller area and also using layers of fleece I would think using a candle would protect your plants for a few -degrees, if you do try it I would suggest that you get a thicker candle, which evidently would burn longer, put a screw into the centre of the bottom and float if in a jar or tin of water which gives you a longer burn and a fire prevention if it got nocked over

[peanut]

Thanks for all your tips and advice everyone. I haven't got round to trying it yet but will eventually!

[DannyK]

Years ago I put 6pt plastic milk bottles of water around the edges of my green houses.. These would act as heat reservoirs.
I have no idea on their effectiveness but they cost nothing. The only problem is they go brittle eventually.

[rary]

Reading Dannyk's post reminded me of a talk by an organic apple grower I listened to once, to protect the apple blossom from frost, he used water containers painted black as storage heaters, so if you get a lot of sunshine in Cambridgeshire it might be worth trying Dannyk's suggestion