Discussion forum for the various methods and structures used for getting an early start on your growing season, extending it for several weeks or even year 'round.
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#1 |
Tomatovillian™
Join Date: Oct 2014
Location: Norway
Posts: 1,049
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I'm considering adding a second layer of LEXAN 6 mm 2-wall polycarbonate sheets (as described here: http://sfs.sabic.eu/product/lexan-thermoclear-sheet/ ) to my greenhouse. As I understand it, the "UV resistance" is there to protect the polycarbonate. What I'm wondering is, will the added UV resistance be detrimental to the growth of tomato plants?
Steve |
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#2 |
Tomatovillian™
Join Date: May 2012
Location: massachusetts
Posts: 1,710
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One polycarbonate sheet will eliminate almost all light below 400nm.
Adding a second sheet cannot reduce this further. However if one sheet has 80% transmission in the spectrum you want, two sheets will cut that to 64%. This would not hurt in the spring, but can be an issue in the fall and winter when the sun is low and weak. Hope that helps. |
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#3 | |
Tomatovillian™
Join Date: Oct 2014
Location: Norway
Posts: 1,049
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#4 |
Tomatovillian™
Join Date: Jun 2012
Location: Illinois, zone 6
Posts: 8,407
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Plants grow fine indoors under artificial lights, with zero UV rays.
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#5 |
Tomatovillian™
Join Date: Oct 2014
Location: Norway
Posts: 1,049
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I only grow in the greenhouse from spring until fall using some heat, but no artificial lighting. Our days summer days are very long beginning fairly early, and I have a problem with overheating, so I think a slight reduction in light could be beneficial. I did, however, read somewhere that UV affects taste positively. (I haven't been able to find out how much the UV is reduced by the polycarbonate.)
Steve |
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#6 | |
Tomatovillian™
Join Date: May 2012
Location: massachusetts
Posts: 1,710
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graph near bottom of page https://www.google.com/url?sa=i&rct=...68763364890220 |
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#7 |
Tomatovillian™
Join Date: Jan 2010
Location: North Central Florida
Posts: 110
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Usually only 1 side is treated for UV. Make sure not to put any sheets backward because it will turn yellow.
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#8 | ||
Tomatovillian™
Join Date: Feb 2006
Location: Den of Drunken Fools
Posts: 38,539
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Plants dont need UV light. Quote:
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