Green polytunnels?

[annie trip]

Hi everyone am wondering (dreaming) of polytunnels. Am after one for xmas but oh thinks a green one would stand out less than a white/clear one.

Not seen many green is this for any particular reason??

[martini]

Green wouldn't transmit as much light and I imagine it would be a bit weird working inside one !

[Snadger]

I think I know the ones you mean and I would imagine they are treated so that ultra-violet light doesn't break down the plastic.They would also stop any scorching of plants from direct sunlight.
I think for growing stuff through the winter months though clear plastic or glass would be better as there is a shortage of light to start with!
Depends when and what you want to grow really

[Earthbabe]

I was looking at one of these too mainly for extending the season a little for toms, cukes etc. I suppose that would work. It would also be used for some early propagating. Do you think the lower transmission of light would matter here.

I used some "green" mini greenhouses (Kays sell them as cold frames) last year and everything seemed to be ok. Even the weeds were fine!

[nick the grief]

The main problem with coloured plastics is they don't transmit as much light. Not a pronlem in the hieght of summer but A poly tunnel or Greenhouse will extend your growing season by about 6 weeks either end of the year. And this is where you would run into problems.

There isn't much piont in growing stuff if it's going to end up weedy because it's got poor light, it will probably succumb to al manner of pests & disease.

Polytunnels aren't the prettiest looking peice of equipment but you can always have some trellis infront of it (say about 6feet away) & grow stuff up that to camoflague it a bit. this would also give you somewhere to store stuff too.

Greenhouses are probable less of an eyesore but there again you'll pay £400ish for a 18ft x 10 ft polytunnel my 12'x8' greenhouse cost me well over that !

[JennieAtkinson]

I thought long and hard about going for green plastic, because apparently it is stronger. But given that what you really want is the longest growing season, more light makes more sense. Although I notice that the suppliers reckon you dont lose that much ???

I've got my Tunnel in the lower part of the field next to the house and have planted a curved bed of willow and honeysuckle a reasonable distance away, which gives shelter from the north and west as well as making it look better. When they go up they are a bit "in your face", but you soon get used to it. (And it wouldn't really matter what mine looked like coz I just LOVE it to bits!)

[nick the grief]

Just for interest this is the claimed light transmission % for various materials

Glazing Material
PMMA (acrylic) 91-93
Sheet glass 88-90
Polycarbonate 82-89
PVC** 76-89
GRP** 76-85

So I would have thought that Green PVC would be around 70-80%

[Earthbabe]

Nick as usual you've blinded me with jargon (or is that science?)! What is GRP and what is the diff between PMMA, PVC and GRP. I know what glass and polycarbonate are though.

[nick the grief]

bugger, I was hoping someone wouldn't ask that

GRP is glass re-enforced plastic (fibreglass to us mortals)
PVC is what polytunnels are covered in (poly vinyl chloride)
& PMMA is er ...um .... where's google ... Polymethyl methacrylate or as it say in brackets Acrylic which is the plastic sheeting that some greenhouses are glazed with,

[Earthbabe]

Thanks nick, sorry to have overtaxed the google finger.