greenhouse problem--need your input

[nodak3]

The sun is causing our polycarbonate greenhouse to turn very yellow.

That admits less light, meaning less growth.

Anything better than polycarbonate for high altitude greenhouses?

[Farmerwilly2]

How long have they been up? I'm putting mine up and I'm still leaning toward glass instead of poly.

[Just Cliff]

Originally Posted by nodak3

The sun is causing our polycarbonate greenhouse to turn very yellow.

That admits less light, meaning less growth.

Anything better than polycarbonate for high altitude greenhouses?

UV inhibited greenhouse plastic. Not sure what kind of greenhouse you have but, you can use it on any type greenhouse I have seen. It usually lasts 4-5 years but, I have a friend that kept it on his commercial greenhouse for 8 years.
The first link is my greenhouse pics:
http://s961.photobucket.com/albums/a...ouse018.jpg%26

This is where I get mine:
http://www.littlegreenhouse.com/accessories.shtml

[pancho]

You could remove it for the summer and use it only when it is cold.

[Just Cliff]

Originally Posted by pancho

You could remove it for the summer and use it only when it is cold.

A greenhouse is for more than growing plants. In the summer after you have removed your seedlings you can dry clothes,vegatables,firewood and can get a heck of a tan without the neighbors looking at you

[nodak3]

We are at an altitude of just over 6500--so much shredding small hail we use it to be sure we get some peppers and tomatoes.

The poly has lasted about 5 years. Lots of small holes from hail now, and as I said, very yellow.

Our high altitude makes the sun more of a problem than it is at lower altitudes, I'm sure.

Overall we like the greenhouse, just wondering if there is a better product to replace the poly with.

[whatrset]

Sounds like your poly is at the end of it's life. I wouldn't think altitude would effect sun intensity, as the same amount of sunlight falls up high as falls down below.

[pancho]

Originally Posted by Just Cliff

A greenhouse is for more than growing plants. In the summer after you have removed your seedlings you can dry clothes,vegatables,firewood and can get a heck of a tan without the neighbors looking at you

You can still do all of those without the top on it. Try it, I do every year.

[Marcia in MT]

How old is your polycarbonate?

We have double walled polycarbonate (Polygal) on our greenhouses, and after 12+ years, it still is as clear as the day we put it up. It's supposed to have a 30 year lifespan, but at another place across town, the 23 year old stuff is turning yellow.

Perhaps you should contact the manufacturer and see what they tell you.

[nodak3]

Good idea, Marcia.

Whatrset--yes, high altitude sun is much more intense in the uv spectrum.

Which is why when you come to the Colorado mountains in the summer you see all these Texans with sunburns.

[byexample]

The polycarb panels I've worked with have a UV coated side that's supposed to be faced out. If faced in, the panels will yellow. Perhaps your polycarb panels weren't installed with the UV coating out and that's why they yellowed?

We have some 5 year old polycarb panels we're using that we recycled out of a greenhouse kit that the wind and sun destroyed (our neighbors bought it). They still look fine and we're at 5500 feet above sea level. But we've been real careful to make sure the UV coating is facing the proper direction.

[ronbre]

i have had a polycarbonate greenhouse up for over 20 years with no yellowing, i'd call the manufacture, probably some bad materials..they should be sunproof