Aluminet shade covers for greenhouse

[maggiepie]

Am wondering if anyone uses this for their greenhouse or alpine house and if so, how effective is it?
I have a small 6X8 ft greenhouse which unfortunately, is in full sun on a cement block.
It gets really hot in summer which makes it almost useless for most of the summer months. The aluminet shadecloth is 'supposed' to cut the temps down by a huge amount.

[Lori S.]

This is not answering your question at all, Helen, but I was just wondering what do you use your greenhouse for?  Using our greenhouse for water lilies, heat-loving things like tomatoes, and various semi-tropicals and tropicals, we've not found any need to provide shade at all (despite the very sunny conditions here) - the more sun, the better.   There is a thermostatically-controlled air-exchanger fan that comes on to control the temperature by pushing hot air out (as, for example, tomatoes don't do well above a certain temperature).  Does your have a fan?

[maggiepie]

Lori, my little greenhouse doesn't have a fan. It has a window in the roof, a vent at each end plus I leave the door open.
I would like to be able to leave some of my hot peppers inside for summer.
I'd also like to be able to leave some clematis seedlings in there until fall. I can put trays on the floor and mist a few times during really hot weather but then I get carpenter ants getting into the pots.

[Lori S.]

We use ours to grow peppers too... another one of those heat-loving veggies that don't do well outdoors here.  We've also grown the odd clematis in it throughout the season (in pots but rooting into the basal gravel) and they don't suffer from the heat or sun.  Getting a heat-exchanger fan sounds like it might be the ultimate answer...  (depending, of course, on many things... comparative cost perhaps being one...)  

(Pardon me but I can't help but think that getting shades for a greenhouse sort of defeats the purpose... people do that here too, though.. but, hey, that's just me, and I admit that I am deeply puzzled by a great many things.   ... Unless maybe one is using it more sort of as alpine houses seem to be used in soggy climates, to keep the wet off... ?)

[Maggi Young]

I cannot help Helen with her Aluminet covers, but I can tell Lori that even in Scotland, which many will tell you is permanently in shade, there are a great many folks who shade their glasshouses.
Even in a country like ours where sunshine and high temperaturtes are not as regular as we might sometimes wish, there is still a likelihood of some crops or even alpines, being scorched in an unshaded house.
Having mostly bulbs in our glasshouses these days, this is not something that much concerns the BD and I... but others paint the glass or use covers.

[Lori S.]

Maggi, not that this addresses "sunscorch" but just to satisfy my curiosity... from previous glasshouse/alpine house discussions here, I got the impression that fans are not standard equipment there in such structures? 

[Maggi Young]

Most alpine and bulb growers have fans, Lori, we have in our houses, but I find it rather surprising that most other growers, those using their "domestic" glasshouses for crops seem not to have fans.  None of my relatives ever had fans in their glasshouses, whether they were growing food crops or ornamentals....but then again, I don't remember any of them having any electricity in them,  either! So there was often a clue, I guess?!!

[Anthony Darby]

How about orientation of greenhouses? I think the rule of thumb is, for orchids and alpines: north-south; for tomatoes etc.: east-west.