Greenhouse Heating

Davesnave

kazwookie wrote: »

Just had to have a fiddle with my wicks when refilling the heater



Go back the floowing lunch time to see how things are going



Green house is covered in black soot, heater is out



Had to spend the weekend power washing it out



Moral of the story, don't fiddle with your wicks.



:rotfl:

I think the moral is 'go electric' myself!

Since writing the stuff earlier in this thread, I've sold my house and 2/3 of the garden, but I still own the 1/3 surrounding the greenhouse. This means that I have water, but my electric supply has gone!

I've taken the attitude that whatever survives without heat, I'll keep. Despite the hard frosts, I've lost very little, and the only protection I've used is bubble insulation, fleece and some aluminium 'space blankets' which I think are used by paramedics for accident victims in shock.

Plants that have come through a bit battered, but alive, include agave,various succulents, scented pelargonium, alogyne and various abutilons. All the tenderish salvias are fine too. The lettuce went rotten, but I'm already enjoying the rocket and land cress, which never stopped growing.

bees2306

Hi
I have inherited large greenhouse this spring 20 x 12 now its coming up to winter I need to know the best way of heating it.
This is the first time I will be using a greenhouse over winter
I am growing a lot of perennial plants for next year and have a lot of seedlings in trays.
I would like the cheapest safest way?
what size heater would I need for this size greenhouse or would I need two?
Are parafin ok as someone told me they are harmful to plants?
also halogen heaters are cheap to run but are they safe to use in greenhouse?
Also could you use a parafin heater one end and a fan heater the other to save on costs.
Any help/tips on any of he above will be gratefully appreciated.

A._Badger

bees2306 wrote: »

Hi
I have inherited large greenhouse this spring 20 x 12 now its coming up to winter I need to know the best way of heating it.
This is the first time I will be using a greenhouse over winter
I am growing a lot of perennial plants for next year and have a lot of seedlings in trays.
I would like the cheapest safest way?
what size heater would I need for this size greenhouse or would I need two?
Are parafin ok as someone told me they are harmful to plants?
also halogen heaters are cheap to run but are they safe to use in greenhouse?
Also could you use a parafin heater one end and a fan heater the other to save on costs.
Any help/tips on any of he above will be gratefully appreciated.

That size of glasshouse is going to be very expensive to heat, however you do it.

First, you have to decide what you mean by 'heating'. Do you want it just frost free, or heated sufficiently to grow a wide range of plants? The former is going to hurt when the bills come in!

My advice would be, first, look to your insulation. You need bubblewrap (get the UV stabilised kind) and apply it everywhere - except over the vents. You'd be surprised how often they will need to be opened in the average British winter.

As for heating, whoever told you paraffin damages plant was about as wrong as it is possible to be. Properly burned, paraffin produces water and CO2 - just what your plants need, in fact. The catch is in the 'properly burned' part.

To heat a 20 x 12 greenhouse you would need a whopping paraffin heater - even just to reliably keep it frost free. This would be both expensive to run (paraffin is no longer cheap) and very time consuming and fiddly to operate. It is also very uncontrollable, being either on or off.

Your best bet would probably be a good quality electric fan heater or two with a reliable thermostat. This would only run when you need it and is clean, safe and reliable - providing you have electricity available.

There is one other possibility. In recent years, quite a few gas heaters have appeared on the market, running from bottled gas. I haven't looked into it personally, but it may be a cheaper alternative to electricity. It has the advantage that, like electricity, it's thermostatically controlled so it isn't running when you don't need it.

But as I said at the start, it's going to be costly, however you do it - especially if you want to maintain a high temperature in the depths of winter.

Possibly better would be to set aside a small area for very tender plants and make a microclimate for them, using a bench heater (perhaps an electric heating mat, or heating wires in sand-filled tray, with a clear cover over the top) and just aim to keep the rest of the house frost free with a fan heater.

There's a lot to think about there, so you're in for a period of research and shopping, I'm afraid.

Hope that helps.

Davesnave

See Post 42. Wasn't last winter though!

Do you need to heat at all? Depends what the perennial plants are, I suppose.