Currently, they are commercially available in a variety of sizes and wattages, color temperatures and spectral compositions. Color temperature qualifies the hue of light and is measured in Kelvin. It is interesting to know that the daylight of the sun exceeds 5000 Kelvin. Color temperature is an important fact, both in indoor cultivation and in other fields. Today there are different types of lamps, which allow to satisfy any light requirement. Their small size - and the fact that they emit many lumens - allow them to grow compact green plants and flowers / fruits. HPS grow lights have a high efficiency, in terms of converting electrical energy into light energy, and the intensity of the light decreases more slowly over time unlike fluorescent CFLs. Their average duration is 30,000 hours of use.
Kelvin degrees
What are Kelvin degrees?
Kelvin degrees are the light temperature measurement system and determine the influence that light will have on white, where zero is placed at physical absolute zero (-273 \ ^ C). A solid body begins to emit light when it is heated to around 753 K (500 ^ C) and emits a dominant red light spectrum; increasing the temperature the light spectrum will take on a green cast, at higher temperatures there will be a blue cast up to ultraviolet and the fusion of the solid body. Kelvin degrees are used in agriculture to indicate the color temperatures of greenhouse lamps. If the dominant color of the light tends to red it is called warm tone (Warm), if the emitted color tends to blue it is called cold light (Cool). Sodium vapor lamps (HPS) have a calibration of about 2000 ° K to rise, while metal halide lamps (MH) have a temperature of over 5500 ° K very similar to the temperature of sunlight.
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KELVIN DEGREES
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1500°K
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Candle light
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Warm
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1800°K
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Sunset
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Warm
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2100°K
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HPS - Sodium Vapor Lamp
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Warm
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2700°K
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Incandescent Light Bulb
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Warm
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2800°K
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Fluorescent lamp
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Warm
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3000°K
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Halogen lamp
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Warm
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4000°K
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White fluorescent lamp
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Neutral
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5000°K
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Twelve o'clock-Noon
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Cold
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6000°K
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Mercury Vapor Lamp
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Cold
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6500°K
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Fluorescent neon tube
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Cold
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Understanding Kelvin Gradation (°K)
How to decide the color temperature (° K)?
The color temperature of an indoor grow light is a simple thing to decide. First of all you need to know what stage of life the plant is in, then decide between the three main categories on the market:
VEGETATIVE GROWTH PHASE: in this phase of plant growth, the light of the lamp must be cold white, between 4000K ° and 6500K ° (480nm). This shade emitted by the lamp facilitates the growth of the plant, which - in this way - becomes beautifully compact. But that's not all, because this white shade allows the plants to also reduce the distance between the internodes and facilitates the development of the most important parts of the structure, such as the stem and leaves. This shade of white is perfect for the growing photoperiod, which needs 18 consecutive hours of light and 6 hours of darkness.
FLOWERING PHASE: the light - in this phase of the plant's development - is yellowish, around 2700K ° (655nm). Thanks to this shade, the plant is induced to develop its flowers more quickly and is perfect if used during the photoperiod of flowering, which provides 12 consecutive hours of light and 12 hours of darkness.
AGRO SPECTRUM, GROWTH AND FLOWERING: in this case, the color and intensity of the light emitted by the lamp can be associated with that generated by a typical lamp for the flowering phase. However, this also partially emits a spectrum of cold white light; which is around 2000K °. In this way there are two products in one: it can be used effectively as a vegetative lamp (18 hours of light and 6 of darkness) and - at the same time - it can also be used during the flowering period of the plant, when the hours of needed are 12.