tina wrote:

Hi,

I have an 8ft x 4ft greenhouse and would like to add a heater to keep
out the cold.
I thought it best to get an OIL filled one rather than the electric
fan type.

I see they go in W rating from 1000w, 1500w, 2000w & 2500w.

Can anyone advise me what size is best?

I'm growing peas, tomatoes & carrots.

Thanks

I use a parafin heater in an 8x6 greenhouse, and it can maintain the
greenhouse frost free without insulation, or keep it 5+C nearly all winter
with bubblewrap. The heater has two chimneys with two wicks in each chimney
and cost about £30 a few years ago. This has proved to be very economical
to run, and very effective. I've got a greenhouse full of lemon/citrus
trees, pineapples, bananas, aloes, and a few other exotics.

All seem quite happy, and have been for many years, in fact me only bought
citrus is growing both calamondin oranges above the graft and lemons below
the graft, a most amusing plant, esp. considering the GC was throwing it
out about 5 years ago because they hadn't bothered to water it :-)

Duncan