Some manufacturers promote that their green colored fabric is best for turf growth. The problem with green colored fabric is that it produces green light under the cover. Studies show that green light can seriously harm plants. Plants grow best under white light which is the light that the sun gives off, when the sun shines on green fabric the light under the cover is green. Please read below for studies of light and plant growth.
"Green Light Can Be Harmful. Professor Kevin Folta of the University of Florida has produced experiments in which plants' development, especially as seedlings, is actually harmed by green light. Specifically, he found that green light can reverse the stem growth in certain plants." www.ehow.com
"Green Light Stops Plant Progress. Daniel Mosquin, the education and technology manager for the University of British Columbia Botanical Garden and Centre for Plant Research, also gave as his opinion that green light, though it might not cause plants to actually die, will have detrimental effects because of the lack of photosynthesis that will result" www.ehow.com
"The beans in green light appeared weakest with pale yellow leaves and thin stems. Green light had the worst effect probably because green light did not get fully absorbed by the bean plant since the plant pigment, chlorophyll, reflected green light." California State Science Fair Project www.usc.edu