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Greenhouse Heating

With gas and electricity prices on the increase also petrol which will have a knock on effect onto every other form of heating are you going to still heat your greenhouse this year.

I would like your views on the best cost efficient system of heating a green house is a thermostatic controlled better that say a Paraffin heater are you looking at solar powered heating.


Also does the cost of heating outweigh the performance of growing your plants?

At what temperature do you switch or light your heating system.




  • Busy-LizzieBusy-Lizzie Posts: 15,096

    I only use my GH from March to start off bedding plants in heated propogaters and later to grow tomatoes in. It gets very cold in winter, living in Dordogne it is often -10° at night, so I don't feel it's worth heating it in winter or growing anything that needs winter heat. I also have a warming cable, buried in sand in an old plastic dog bed in the GH which I put newly germinated plants into. It doesn't use much electricity and it keeps them free from frost and a bit warmer at night.

    Dordogne and Norfolk
  • With no affordable way to get electricity to my greenhouse for thermostatic heating (which would definitely be my preference) I am going to stick to my old-fashioned Aladdin Paraffin heaters this year but from lessons learned from last year am going to use fleece instead of bubblewrapping the glass because the paraffin causes a lot of damp. Also, I'm aiming at a sort of cold greenhouse this year. I will only aim to heat if the temperature drops below zero and will deal with the more tender plants by having coldframes inside the greenhouse to create a double-glazed effect.  Fingers crossed, that will work. image  Last year I found I had molly-coddled my plants a little too much and with the cold spring ended up struggling to harden stuff off enough to plant outside.  It got to the point I had so many plants still inside when I was trying to get the summer bedding sown that I had to buy a ton of cheap staging to utilise all the height of the greenhouse and then it was murder trying to water everything when I could barely squeeze inside between the racking.

  • I don't heat mine at all but stock it with containers filled with water which supposedly increase in temperature during the day and then keep the interior a bit warmer at night as a result, taking time to lose the heat gained.

  • nutcutletnutcutlet PeterboroughPosts: 26,160

    I don't heat mine. I've thought about it but on balance I think not

    I don't grown much that would benefit

    Electric subject to power cuts when you need it most

    Paraffin, unreliable, wet

    Bottled gas, expensive 

  • BB thats a big parafin heater 10ftx8 ?


  • hee hee got you BB I know it was the greenhouse that was 10x8 but soory just couldn't stop myself sorry.


    what is unreliable a bout a parafin heater by thet way is it that they just go out ??


  • Tropical SamTropical Sam Posts: 1,488

    Even if there was such as thing as solar powered heating, for 3-4 months of the year daylight duration, angle and strength would render it useless. The coldest period is 3am-7am in winter. On Dec 21st it can be daylight only from 9am-4pm, so solar will never work.

    If you mean some sort of heat exchange using water warmed by the sun, then again the above with the added complication that the water will freeze to some extent.

    An electric fan heated with a thermostat set to 7C is probably the best value given that paraffin produces so much moisture and you can kill more with botrytis than cold.

  • Thankyou blairs I will look into this 

    I did see a fan greenhouse heater in this months GW near the back page


  • Tropical SamTropical Sam Posts: 1,488
    CluelessGardener wrote (see)

    Thankyou blairs I will look into this 

    I did see a fan greenhouse heater in this months GW near the back page


    Have a look on Amazon warehouse - they often have cheap electric fan heaters with thermostats for half price. I would say it cost about £20 more to use it last year and that was with those late frosts James!

    I would only say it was cost effective if you already have electricty in the GH of course as it costs loads to instal with trenching etc.

  • I have put electricty in the greenhouse footings also a water supply so I'm all set and ready for Mr J frost.



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