Greenhouse Heating ?

[Skipper]

Advice please
We are about to buy a new 10x12 greenhouse---(sold the family silver). Can anybody advise us on what might be the cheapest form of heating it? after spending out on it it will have to watch the penniesand the way the cost of things keep rising nowadays could end up living in it

[Starchild]

I'm am spending quite a bit on heating my greenhouse. I am buying a solar "power station" (can be charged via panels or by recharge from mains) that will run 2 of those in car ceramic dashboard heaters and using that to keep the frost off. £200 outlay but no or very little running costs.

[Iaind4]

Try looking at a thermo tubular heater, a 5ft long 300 Watt one would cost you about £19.00 , plug it into a timer for off and on to suit the time of year etc, should do the trick.
Dose for me in Aberdeen Scotland.

[Skipper]

Thank you Starchild and Iaind4 for your help,I think we will go with electric heating as suggested rather than paraffin.hope the season is going well for you both

[Alice]

Hello Skipper, I don't think you would be happy with parafin - creates more problems than it solves.
I used an electric fan heater. Don't know what the heating cost but wasn't astronomical. It's very controllable giving you just the temperature you want and helps with air circulation and ventilation too.

[Kristen]

Couple of thoughts:

Insulate the greenhouse with bubblewrap?

Gas bottle or electric can be controlled with a thermostat. I don't think you can dot hat with paraffin

With regard to the family silver sale unless you are particularly looking for a shiny brand new one, you might like to look on eBay. I bought a 30' x 10' aluminium Eden greenhouse less than 5 years old for £400. I had to go and dismantle it, but that only took me and my mate about 3 hours, and it made a nice day out!

[Two_Sheds]

Why bother? Are you growing tropicals?
We use a cold greenhouse for everything: we start off the veg in about Feb/March in the greenhouse. It is frost free (we don't get much frost here on the East Coast anyway)

[Alice]

Everybody is not frost free in February Two Sheds. We all have to manage with the conditions we have..

[Skipper]

Thanks all for your help.We have decided to go for electric heating as it does seem to be the best, it does get a bit nippy here during the winter months,I also want to use it to bring on plants earlier than we would do normaly and so extend our growing season.

[Gwyndy]

We use electric heating Skipper but I have a very accurate and sensitive thermostat set so that it just keeps the greenhouse frost free. You will notice the effect on your electricity consumption during very cold spells but if you use the heating just as a frost protection measure the cost is tolerable. I also built a propagator box with a soil warming cable and thermostat and this is very useful for protecting small plants, new cuttings, etc.

I used to have a paraffin heater but you had to guess what the weather was going to do overnight and then decide whether to light it or not. It also generates a lot of moisture when burning so daytime ventilation was important to prevent mildew. I was glad to get rid of it when I installed the power supply to the greenhouse.

[SarzWix]

I use electric in our small g/house at home (it's only 6'x4') and find that our electric consumption goes up considerably! It all depends on what you want to achieve - if you want to put tomatoes plants, bean plants etc in there in April/early May, you'll need to heat it to at least 10°c to keep them growing. If you just want frost-free, suitable for brassicas & early peas, then you'll be aiming for around 5°c which is a bit cheaper to maintain.
For our allotment greenhouse (12'x6'), I've invested in a gas heater. This cost £100 plus the deposit on the gas bottle & the actual gas - initial outlay of £150 altogether. However the gas lasted for over 2 months (& still some left in bottle) working out at less than £10 per month for running costs, considerably cheaper than the electric used to heat a space a 3rd of the size!

[Kristen]

I have two mini greenhouses (the cheapo things that are just a frame and a flimsy plastic cover with a zip) that I used as [what I think are called] closed-boxes. These are against the West facing wall of my conservatory, so get no direct sun until around 2pm. These get seedlings, plants when first planted out, cuttings, etc. and I spray them frequently and keep the zip-door zipped, or just let down, to keep them warmer. They are significantly warmer at night.

So, long winded way of saving, if you can concentrate your plants in the early stages of spring, you may be able to localise the heat, and thus reduce the fuel cost. A sheet of plastic blocking off the end of the GHouse may be enough.

Personally I like the idea of the electric tube heaters. Putting them underneath the staging localises the heat to the plant roots, which is most important for early growth and warding off frost/cold. Bit like the old Victorians hot water pipes did. So I would favour that over a fan heater approach. But I don't have electricity anywhere near my greenhouse