Color Matters - The Amazing Science of Color

Science Projects - FAQs

Color and Heat Absorption
Does the color of water affect its evaporation rate?
Is plant growth affected by light color?
Does color affect taste?

Is plant growth affected by light color?

the color of light and plants

Question: I need help with an experiment I'm doing. I read some place that plants need more red artificial light because it is the color of heat. It also said that artificial blue light was a cool color.

Jenni (a former student of SAS, a China located international school)

Yes, it is.... and here are a few sites to help, as well:

Does Colored Light Affect Seed Growth

How Light Affects Plant Growth

Does the Color of Light Affect a Plant's Growth

See, sunlight contains many colors of the visible specturm, and the unvisible. Plants can be affected. Cellophane tents don't work because they don't supply the correct amount and cellophane affects opaqueness of the light... so use colored light bulbs. Plants (expecially flowering and house) tend to like violet, blue and red lights... not so much as some yellows, oranges and greens. Maybe this should help... Good LUCK!!!! -Jenni,

Mac
Cynthia, John Ott worked a great deal with plants and how light and color affects them. I suggest you read some of his work. You can find references to John Ott on the web (Editorn note: use the search engines) etc. I suspect it's not the color 'temperatures' you'll find to be central, but the frequencies of light that come in contact with the plants. You can do literature searches on such topics as color, temperature, and plants. But conducting an experiment gives you direct experience and first hand observations. That's what scientists like! :-) Conduct your own experiment - and maybe you'll find something never before discovered.

The 'color' of light (the emission amplitude and spectral distribution) can significantly affect plant growth. Keep in mind, it's not only the visible light, but the UV and infra-red areas in the spectrum - light that is not visible to the human eye. There are 'full spectrum' light bulbs that have been available (at least in the past) for people who wish to provide 'sun equivalent' lighting forplants [and people too] - both plants and people probably grow better :) under this type of balanced light. As an aside, the typical cool white fluorescent lamp emits strongly in the blue and green emission bands (try peeking at one with a prism or spectra scope.) Studies have suggested that fluorescent and other unbalanced bulbs do less than great things of people and plants are exposed to them chronically (prolonged exposure).....including 1. increased incidence of dental caries (cavities), 2. hyperactivity and depression in adults...on and on... To answer your question though, yes, light affects plants. It can inhibit growth, reproduction, and plant health.. ...or help it if the light is right. Regards, Mac

amc
You might want to look on the web or in a bookstore and find a few books written by John Ott. He did some plant and colored light stuff - kinda like you are! :) Cool eh? Then - don't believe everything you read. Do the project yourself! Get some plants, buy some little lights, and away you go. (Psst - go ahead and do the Red, Blue, White, and Yellow - but add a few more lights if you can. A so-called Gro-Light that has some UV in it - and perhaps a standard fluorescent bulb.)

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