The natural light being in a variation of red orange and blue and electrical light being white.
Because light gets screwed up in the matrix. Actually sunlight is made up of all colors vs electric light which is not.
It will, but be warned. You need a really powerful torch to see any reaction. You might try working with a shade-type plant, like a small house plant and maybe a larger source of light, like a modified heat lamp. Garden shops have green house lights that would work splendidly. You know what's another cool project? watching flowers bend toward the torch in the dark. It's really cool.
Natural light is from the Sun, which puts out a full complement of colors (icluding ones we can't see like ultraviolet). Electric lights put out a lot of red, orange and yellow, and very little to the blue end of the spectrum.
Though the previous answers are somewhat true regarding the most commonly used light bulbs, the premise is not entirely true. Depending on what sorts of gases are enclosed and what phosphors (the powder coatings inside fluorescent lamps) are used in a man-made light source, synthetic electric light CAN be generated that is visually identical to sunlight. There are dozens of color temperatures available in light bulbs these days -- some are used in film-making to simulate sunlight for indoor scenes, others are used to make merchandise more attractive in stores or to grow plants. The main difference between sunlight and electric light is the overall intensity. You get thousands of footcandles (a standard measurement of light) from direct sunshine whereas a well-lit office space is only about 75 to 100 footcandles per square foot.