My New Greenhouse :)

It depends on the species @JWK, Some grow at very high altitudes in the Andes etc and are even covered in snow for part of the winter. Most deserts become extremely cold at night anyway.
They survive because the ground is dry. That's why it is best not to water them from November to March.

 

We tend to keep our greenhouse just frost free at 3c, though most typical electrical fan heaters have rather crude bi metal thermostats that can waste a lot of electricity by having such a wide on / off range.

Using an electronic thermostat gives much more even results typically to within 1c.
Many on the market, and with todays energy prices they would soon pay for themselves, this looks handy with a long sensor lead.

Likewise we are getting condensation on our polycarb roof, but not really causing much of a problem with drips.

 

Thank you @ricky101 I will have to get something like that. At the moment all I've got is an ordinary heater for a shed. I put it on a timer and it comes on for an hour or two, very low, in the early hours. However, I haven't needed to use it for several years and I suppose I'd become used to recent very mild winters.
I'll see what I can get ... I must have clicked a strange button by mistake for the letters to come out like this

 

@Michael Hewett if you hit the CTRL key simultaneously with the I, it starts using italic, and if you hit CTRL (or the text buttons above) and I again, it turns it off.

Ctrl I then off again and Ctrl B makes bold and ctrl U underlines and on and on and on!

 

@Michael Hewett I have found that keeping fans running to circulate the air stop condensation from form at the peaks in my little greenhouses. Perhaps a little one pointed at the ceiling would help?

 

Thank you @CanadianLori

 

I think condensation is everyone's nightmare at this time of year.
The greenhouse I have cacti in gets the door open whenever the temperature is above freezing.
Probably not so good if you have any rare ones from tropical parts but I prefer to clear the condensation every day if possible and the only way to do that is not have a temperature difference between inside and out.

 

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I open the door and windows on dry days but not in this weather. I keep the tropical cacti in the house.
I haven't tried clearing the condensation, there's such a lot of it, and the greenhouse is new. I haven't had one since I was in my 20s. How do you clear it ?

 

My greenhouse at this time of the year is just used for keeping plants alive, I really dont want anything growing, so during the day any positive temperatures are OK.
If I wanted to grow anything at this time of the year I would section off part of the greenhouse and heat that to a higher temperature.
Something I've not done in years.
I prefer it to be coldish rather than wet in there.

 

So many Cacti,Michael

 

That's a good idea, maybe I'll do that as well.

I just use it for my cacti and succulents. Tender perennials are in a perspex shelter at the side of my garage.

I know it's just coming up to 2 a.m. but since Bella cat needed to go out I had a look in the greenhouse to see if the condensation had frozen, and most of it is not so.
I've put a heater to come on for an hour from 3 - 4 o'clock but it may not be needed. Anyway, I left it alone, it was too dark to be fiddling around in there. It's probably about -1 or -2 outside.

 

Just been into our greenhouse which we recently extended with the same type of 10mm twinwall polycarb as the original but also found it dipping so much with condensation the new bench was soaked.
The three original roofing spans had a little condensation on them but nothing like the new span.

Just looked at an offcut of the new polycarb and its Palram SunLite whereas the original is Wickes from about 10 years + ago so cannot remember what brand that was.

Clearly must be some big difference in the insulation qualities, though you would think the newer stuff would be better than the old.

Just looked at Palrams site, seems they do an Anti -condensation version ?!

Wondered what brand yours is and if you are still getting lots of condesation after the cold nights ?

We keep ours at a minimum of 3c.

 

I've got the old Wickes stuff and I do get condensation, its worse in the greenhouse than the porch which is more ventilated due to me going in and out all the time.

I just think its this damp then cold weather, the fluctuating temperatures cause it, everything gets cold, then it goes mild and condensation forms on everything, even the sides of pots and especially on cacti that take a long time to warm up being mostly water.

On days like yesterday when the paths were drying I open everything up, but today is wet, humidity is high and nothing is going to dry out.
Dehumidifier might work but expensive to run these days.

 

I don't know what brand the polycarbonate is, the builders got it for me. It is full of condensation, big drops of it, but they don't fall down unless I try to wipe them off ... then I get a shower ! ... The rest of the greenhouse is dry.
I ventilate it on dry days but the condensation doesn't disappear.





It doesn't get extremely cold in there because there are walls on two sides, one of them being the wall of a utility room in the house. The other wall is a boundary wall between two gardens. The windows are double glazed. The builders looked into it and said single glazed windows were actually more expensive.

I am going to wipe the condensation off one day but I have to cover the plants first. I don't think cacti and succulents would appreciate having a cold shower in January.

I wish I'd known about the anti-condensation version, I could have told the builders about it.

I have a polycarbonate roof on a shelter adjoining the side of my old garage down the garden. I don't think there's any condensation on that (I'll have to have a look tomorrow to make sure)
That makes me think the greenhouse condensation is due to the fact we had very wet weather before the windows were installed, and the floor and walls became wet. They've dried out now but I think the air inside the greenhouse is still damp.