Subject: I am doing an experiment growing marigolds under colored light.

I planted 4 plants under clear, red, yellow and green cellophane.  I found 
information that said red light has the longest wavelength.  It also said 
that waves with shorter wavelengths carry more energy.  I can't find any 
information that will explain why the red plants, with the longest 
wavelength is about 3 cm taller and healthier looking than the others.  
Clear is the smallest.  Where can I find information that I can understand 
as to why this is happening.  I've looked everywhere.  Thank you!

Re: I am doing an experiment growing marigolds under colored light.