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Old 06-10-2005, 11:32 AM
blass blass is offline
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First recorded activity by GardenBanter: Jul 2005
Posts: 11
Wink

Thanks you guys and to Ted for that lengthy insightful piece. To quote from the book, Orchids Of Asia by Teoh Eng Soon, top orchid grower of Singapore, (Chapter 6 on Light)......

"The type of light is also important for the proper growth of orchid. Light in the ultra-violet, near ultra-violet and green ranges represses plant growth, and green PVC sheets are TOTALLY UNSUITED for roofing of orchid houses. When too much green algae collect on top of the plastic roofing, it similarly represses plant growth. The algae must be scrubbed off or the roofing replaced. The simplest approach is to employ shading which will not interfere with the normal spectrum of sunlight, such as with lath houses, white paint over glass, or black saran cloth."

Now comes the subject of the color black in shade net trapping heat efficiently more than the green one. Any takers?