Poly tunnel questions

[Newbiegrower1970]

Why are they opaque?
Do the plants get enough light?
Many thanks

[Jay22]

Do they not do the job of not only regulating light but temperature?

[bario1]

I think the diffuse light helps to avoid leaf-scorch.

[Snadger]

I think polytunnel plastic covers are designed not to break down through sunlight (photosummatorother)

I've never seen a clear version, but imagine if it was clear it would degrade with sunlight?

One of the guys at the allotment tried to wrap his polytunnel in clingfilm, the type used for wrapping pallets! Needless to say, it didn't work out too well

[TrysHard]

I have a Rion Opaque polycarbonate greenhouse it reduce scorch but still lets in around 90% of beneficial light - Poly tunnel are the same effect.

[MarkPelican]

There are completely clear covers but they are brittle. However, I thought that the non-clear ones let through the necessary light frequencies.

Mine (from Solar Tunnels) is covered in green squares (not the cheap ones) and I think I would prefer a standard white plastic one as it definitely cuts down on the light however, its lasted 12 years so far and I haven't felt the need to change it.

As regards temperature, I believe that a glass greenhouse of the same volume won't cool down as fast but a lot of the temperature control comes down to the volume of air so a big polytunnel will regulate the temperature better than a small glass greenhouse.

[land_girl_dani]

diffused and clear polythene

Diffused polythene disperses light so that your plants do not get scorched in strong, direct sunlight. Not too much of a problem in the North of England (where I am) so I would go for a clear polythene. This allows the most amount of light into your polytunnel as possible.

Which one you will need would depend on your average climate and the type of crops you'd be growing. Some plants enjoy full sunlight, others not so much.

Hope that helps!

[Thelma Sanders]

Why are they opaque?
Do the plants get enough light?
Many thanks

Farmers wouldn't use them if they didn't work, would they now?