Ballast - The electrical components (usually a transformer and capacitor) that energize a high intensity bulb.

Color Temperature - (also known as Kelvin temperature or correlated color temperature)  A measure of color of light emitted by a bulb in comparison to black.  This is used as a general measure of a bulb's coolness (whiter light) or warmness (redder light).

Footcandle - A unit of illumination equal to the intensity of one candle at a distance of one foot.  Footcandles are usually used as a measure of light received.

Lumen - A unit of illumination; a measurement of light output.  One lumen is equal to the light emitted by one candle that falls on one square foot of surface located one foot away from the candle.

Photoperiod - The relative hours of light and darkness in a 24-hour period.  Some plants respond to a change in day length (photoperiod) in order to grow or flower.

Photosynthesis - The process by which plants use light energy to collect carbon dioxide from the atmosphere and convert it to chemical (growth) energy in the form of carbohydrates.

General Info

Metal Halide lamps, Mercury Vapor lamps and High Pressure Sodium lamps all belong to the H.I.D. (High Intensity Discharge) family of lights. Metal Halide and High Pressure Sodium lamps are used for garden lighting because of their high light output per watt, and the spectral distribution of their light. Mercury Vapor lamps are NOT used for horticultural purposes due to their poor spectral distribution (useless for plant growth). Following are the various types of lamps that we sell.

Metal Halide / Daylight / MS Lamps - These lamps emphasize the blue / green spectrum to promote vegetative growth. If you have little or no sunlight available these are the systems to use. MS lamps contain a 30% boost over standard Metal Halide lamps in the red/orange spectrum and more lumens per watt than standard Metal Halide lamps. The Super Son Agro (Daylight) bulb is very high in blue spectrum and also high in red/yellow. This makes it an excellent light source for propagation and for supplementing HPS lamps.

High-Pressure Sodium/ Son Agro lamps - These lamps are primarily red/yellow in spectrum. These are the best lamps available for use in conjunction with natural sunlight. High-Pressure Sodium lamps promote budding and flowering in plants. The Son Agro lamps emit 30% more blue spectrum than standard High-Pressure Sodium lamps, thereby reducing inter-nodular elongation of plants. Son Agro lamps are the choice for most professional growers because they are very efficient and contain a balanced spectrum for all stages of growth.

Conversion Bulbs - There are two types:

1) Sodium bulbs which run on Halide ballasts - available for most systems.

2) Halide bulbs which run on Sodium ballasts - available for 400 or 1000 watt systems only.

A conversion bulb lets you tailor the light source to the growth stage of the plant merely by changing lamps.

Fluorescent Lamps - These lights are perfect for starts and seedlings. They are generally a poor light source for production growth and flowering because of their low lumen output, although they may be used in some instances for small scale systems with low growing plants, ie: lettuce, basils, etc. Plant growth will not be as rapid as under HID lighting due to lower light levels.

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