I am beginning a research project for 9th grade biology. I would like to show the effects that various commercially available light bulbs have on plant growth. I am going to buy incandescent, fluorescent, halogen, etc, as well as bulbs specifically engineered for plant growth. I am also going to include information on the commercial use of artificially grown plants, and general information on artificial lighting and plant growth. I would appreciate any information or resources that you could send me.
Sincerely, P. Grasso
Mr Grasso: Thank-you for your inquiry. Incandescent bulbs can be effective for keeping short day plants from flowering by interrupting dark cycles during short days. Fluorescent bulbs are ideal for propagating plants, including seedlings and cuttings. They can also be used to grow shorter, lower light requirement plants such as African Violets. Don’t waste budget money and time on the halogen lights or mercury vapor. Metal halide bulbs (M.H.) are higher in the blue portion of the spectrum, so are ideal for vegetative (spring/summer) growth. High pressure sodium lamps (H.P.S) are more in the red/orange spectrum closer to the harvest sun in autumn. Both metal halide (M.H.) and high pressure sodium bulbs (H.P.S.) are members of the H.I.D. family (high intensity discharge lighting). H.I.D. lights are ideal for commercially produced plants such as roses and other high value crops. There is a lot that can be learned with respect to the ballast core, capacitor, and starter (HPS only) with regards to H.I.D. lighting and electrical principals. Experimenting with the effect of day length and uninterrupted darkness are among the many experiments that could be performed. Far red light also influences germination and dormancy in seeds. Please do not hesitate to contact Max Yield along the way.