Heating my plastic greenhouse

s4lvatore

As of next february/march I will probably be transferring my seedlings from the house into my newly acquired 6x4 plastic greenhouse. I got it for a snip (£10) so am not fussed about buying bubble wrap and an extra cover for it to keep it warm. I have also figured out how to stop it flying off in the wind.

I am only ever so slightly concerned about overnight temperatures in there.

I have no leccy outside nor do I want to use a paraffin heater as I figured it wouldn't really be money saving.

So I have been looking at this. I figured I could probably make one for less than £15 and wouldnt cost me more than a couple of quid a week to use if I get the candles from the pound shop.

Has anyone had any experience with terracotta pots and candles for heating?

sickofusernames

Myself I've bought some tea lights from Wilkinsons which were on offer in the clearance section, 25 candles for 35p each. I used them a few times in my plastic greenhouse by melting about 5 or 6 of the tea lights into a larger glass and making my own wick. This lasted a good 9 hours approx, enough to keep a severe frost at bay.

Wilkinsons sell their normal tea lights at £1.75 for 100 so it's worth looking out for bargains. How many do you get from the pound shop?

s4lvatore

Apparently the opoint in that terracotta pot thing is that the bolt in the middle is what collects the heat and spreads it throughout the pots.

sickofusernames

I'd personally save yourself £15 by making one yourself and just buy loads of tea lights. By my quick calc's, for £15 you could buy yourself about 1000 tea lights which will last you roughly 6 months if used every night for 8'ish hours using my method.

The website mentions it collects soot within the terracotta which is fine if using inside the home but is it really a big deal in a greenhouse, especially a plastic one?

By all means, make one yourself if you like but I'm trying to save you money

s4lvatore

I appreciate that mate, although I have read that you can just put one candle/tealight in an upside down pot for a similar result.

sickofusernames

If it works with just one tea lighter then all well and good but I have my doubts, the only way is to test it...good luck.

s4lvatore

Well they are such a good price at wilkos I could always put 3/4 under a pot, hehe

Lotus-eater

I've used a candle under a large terracotta pot, it works really well.

I use a large candle so it doesn't go out overnight. Kept the frost off just enough in spring for my tomatoes. I wouldn't use tealights overnight as they won't last long enough.

I've looked at this American one before and although it looks like a slightly more efficient design that just sticking a large pot over a candle, I wouldn't think it would make that much difference for the money.
I thought about making one, but never got round to it, last year I only used the method for about 4 or 5 nights, not worth worrying about for that.