How hot?

[piskieinboots]

I heat (warm) my greenhouse using a parafin heater - it keeps it just above freezing, although I found ice in the watering can that is kept in there! So clearly it ain't warm enough.

How hot do you heat yours to, assuming you do heat it?

[zazen999]

I don't, but will be watching the responses as I'm interested in how much it costs and whether it is worth it.

[piskieinboots]

Cost-wise, for me, is approx £7 per week.

I can't say whether it is worth it yet as this is my first year of heating and as we are in the grips of a crackingly cold winter it may not be a good representation.

I can say that all the green stuff in there looks a darn sight cosier than the green (!) stuff outside

[Hazel at the Hill]

What do you have in there, Pisk?

[piskieinboots]

What do you have in there, Pisk?

Broad beans (in the border, just showing through - yaaay)
Herbs (soft ones, in pots)
Leafy salad types (in pots, trays etc)
Hardy annuals
A fair few overwintering floral types
A baby Bay tree

I want to get some toms and chillis on the go, but don't feel that the heat is hot enough. There is no chance to get electricity down to the greenhouse for a propagator, so not sure these will be happy?

[Hazel at the Hill]

Well, the broadies will be okey dokey, but all the others want to be frost free, I guess - have you got a mini greehouse jobby so you can make a 'greenhouse in a greenhouse'?

Or extra bubble wrap round the inside of the whole caboodle - otherwise you're looking at a second/beefier parafin lamp to get the temp up a bit, I would think.

[piskieinboots]

I have it fair heftly bubblewrapped, today the roof is under a very heavy snow blanket - bet that warms it up

[Snadger]

I have a small single burner paraffin heater which gives out a small amount of heat. It lasts for about 8 days on about 2 litres of paraffin.
I think I pay about £13 for 20 litres of paraffin so that works out at about £1.30 a week which I can just about live with.

It gives off about the same heat as a candle and I usually do as Hazel says and have it in the bottom of one of those small placcy greenhouses within my glass greenhouse. I haven't bothered this year though and should really build some type of shroud around it so I am only heating a localised area. Its only to keep the frost off my leeks and chrysanths!

[Nicos]

To boost the heat a little, you could try filling a few large plastic bottles with almost boiling water, and leaving them near the plants.
....repeat several times a day!

[kentvegplot]

I'm trying to keep mine frost free, but at the moment that means all 4 burners alight on the paraffin heater, and on for much of the day as well as the night.

I've been through one 4l container of paraffin this week, but I was also faffing about with a newer, more powerful heater so some of the fuel went in that.

I'd say on average I light the heater 3 times a week from November through to March, and usually burn about 18-20l of fuel over that time. That means about £30-35 for the 5 months, although this year is clearly going to be more. I keep fleece handy for those extra cold nights and, to be honest, nothing in there is going to die if it dips to -1 or so.

[Alison]

I have an electric rod type heater thing on a thermostat in the greenhouse but I've not turned it on for about 4 years as I don't think it's worth it all winter. I do like the fact though that I have the insuranace that if we get a late frost when it's full of tender stuff I can protect it OK. Not sure exactly how much it cost to run, not that much when I'd fully polystyrened the lower level and bubble wrapped above. However it just felt wasteful to me as I only seemed to gain a couple of weeks and so compromise by bringing the citrus trees and a few other things into the conservatory and leave the greenhouse to the likes of the potted peach tree which don't need heat and then protect the winter salads by putting fleece or whatever over as necessary and it seems to work OK although not been down the garden for a couple of days due to the snow.

[Madasafish]

I have three heaters:
a very small one only good for being directly underneath a small plastic greenhouse inside the bigger 8x8 greenhouse. Just to keep off frost. 5 litres of paraffin every two weeks.

a double burner paraffin one which uses 5 litres/week and in spring heats to 5C at night.. (minimum).. Just for small seedlings. March -May. I cover everything with fleece at night.

A blue flame one which gets to 10C at night. 5 litres last 3 days. I can't afford to run it.