Topic: Greenhouse versus summer months

[beanie3]

Hello!

I am venturing into the world of the greenhouse.  I have a plastic lean too between my garage and some decking which after two years i have to admit isnt in the best positioning and only had a few tomatoes....so that is now going to be the wood shed and a new glass greenhouse is being purchased.

So questions.....firstly are there any golden rules of buying, positioning, growing?  Secondly is it true you have to whitewash of bubblewrap the glass in the summer?

All help appreciated.

[Barnowl]

I know there is a point at which a GH is too hot - my mother's is exposed to full sun all day and she paints the glass white. I think bubblewrap would have the wrong effect :)

Ventilation is the key: in a normal summer, unless you are at home during the day I think a vent in the roof operated by an automatic opener is a necessity not a luxury, although it does add to the costs. Side vents are nice to have as well since a good air flow inhibits a lot of GH nasties, although I suppose one could just leave the door ajar.

[Trevor_D]

I bubble-wrap mine in the winter, not the summer. It helps keep it warm.

I have bottom vents which stay open all summer, as does the door. Plus self-opening roof vents: they really are worth the money, and last for years. I have electricity in mine, so in the winter the heating does on by thermostat, but in summer it can double as a fan when it's really hot. And we still end up damping down with a hose or spray.

As for buying - the golden rule is buy one two sizes larger than you think! Site it somewhere sunny and, if possible, close enough to the house to run in both water and electricity.

[Old bird]

Hi Trevor!

The sun - if no shading is added - can scorch the leaves!  I use an old net curtain strung ofver the roof just to tone down the midday sun.

My old mum used to us the paint/spray stuff - which obviously works well but you have to clean it off again at the end of the season and it can make a bit of a mess!

Old Bird

 ;D

[Tee Gee]

I use agro fleece.

In winter it doubles up as an insulator!

Currently I have it over my chitting potatoes, the light gets through to promote chits and it keeps the air around them just a bit warmer than the ambient temperature of the greenhouse.

[Vortex]

I have shade netting in mine which I leave up all year round.

In the summer, it gets the sun (if we have any) from early in the morning until late in the evening. It has 2 double roof vents on automatic openers and if it's likely to be really hot then the door stays open. My next purchase, when I can afford it, is a louvre vent for the end wall opposite the door to help improve circulation when the roof vents are closed.

As to buying one, only do so as a last resort. Keep an eye on your local freecycle they often come up or make your friends aware your looking for one. I got mine from a friend of a friend of my friend - I had to dismantle it and collect it but it was otherwise free.

[Plot69]

I've got a large PC fan fitted into the side of my GH connected to a small solar panel on the roof. The hotter the sun, the faster the fan sucks cooler air in from outside helping to circulate the air inside the GH. The cloudier it is the slower the fan runs... Sort of self regulating really.

[Chrissie]

Hi,

As posted elsewhere I've recently put up a lean-to polycarbonate greenhouse (Norfolk) and it's going to need a lot of shading as the temperature goes up alarmingly when the sun shines, even at this time of year. I've installed a solar ventilation fan which works well but what about the mesh shading you can buy on a roll? How would I attach it? Memories of school physics make me think I should put it on the outside - is that right?

Thanks for any help.

[kt.]

I havejust managed to get a roll of bubble-wrap that was being thrown out yesterday.  Due to the recent and forecast cold spells, I intend to insulate my greenhouse this weekend to aid the seed sowing to keep warm.

[tonybloke]

Hi,As posted elsewhere I've recently put up a lean-to polycarbonate greenhouse (Norfolk) and it's going to need a lot of shading as the temperature goes up alarmingly when the sun shines, even at this time of year. I've installed a solar ventilation fan which works well but what about the mesh shading you can buy on a roll? How would I attach it? Memories of school physics make me think I should put it on the outside - is that right?
Thanks for any help.

yes that's right! place shade net on the outside of the greenhouse. ;)

[Chrissie]

Thanks Tony - any tips on how to fix it?

[tonybloke]

several methods spring to mind. attatch a wooden batten to 2 of the edges, and drape over.,
 Secure with wire / string,
'gaffer tape'
small children? ;D ;D

[Plot69]

Thanks Tony - any tips on how to fix it?

Mine is a tight fit in the hole I cut in the polycarbonate. I made a little box on the outside to protect it from rain with just the underside open and used silicone bath sealer to fix it all.

[northener]

Ingenious. I'm just in the process of rigging 2 propogators to an invertor and car battery. Thinking of using a solar cell for trickle charging the battery.

[Chrissie]

several methods spring to mind. attatch a wooden batten to 2 of the edges, and drape over.,
 Secure with wire / string,
'gaffer tape'
small children? ;D ;D

Thanks, that's brilliant - my children are no longer small but I'll try to borrow someone else's!

[Hosta]

I've got a large PC fan fitted into the side of my GH connected to a small solar panel on the roof. The hotter the sun, the faster the fan sucks cooler air in from outside helping to circulate the air inside the GH. The cloudier it is the slower the fan runs... Sort of self regulating really.

That sounds like a fantastic idea Plot69.  Does it keep the temps down well even on the hottest days ?

[terrier]

Even with the door open and two roof vents open, my greenhouse still got very hot last summer. It gets full sun from late morning 'till late evning, so I'll be using shading this year. The PC fan sounds like a great idea, I'll put that on my 'to do' list  ;)

[Chrissie]

I bought some of that green mesh shading - stapled a "hem" along the top and bottom then slid in garden canes. With a loop of string attached to each end of the top cane I can hang it on the top door rail so it covers two-thirds of the front of the lean-to greenhouse, and the bottom cane keeps it flat. I can still open/close the door behind it and it's easy to put on and take off.