LED lights emit different wavelengths of light based on their color temperature because of the way the LED is constructed and the materials used in its composition. LED stands for "light-emitting diode," and it consists of a semiconductor material that emits light when an electric current passes through it.
The color temperature of an LED light is determined by the bandgap energy of the semiconductor material used in the LED. The bandgap energy is related to the energy levels of electrons within the material. When an electron transitions from a higher energy level to a lower one, it releases energy in the form of light. The color or wavelength of the light emitted depends on the energy difference between the two energy levels.
For plant lights, the wavelength of light is crucial because different wavelengths have different effects on plant growth and development. Photosynthesis, the process by which plants convert light energy into chemical energy, primarily occurs in the visible spectrum of light. However, different wavelengths within the visible spectrum have varying effects on plant growth.
Plants primarily absorb light in the red and blue regions of the spectrum. Red light, with a wavelength of around 620-700 nanometers (nm), is essential for promoting flowering and fruiting in plants. Blue light, with a wavelength of around 400-500 nm, is crucial for promoting vegetative growth, including leaf development and root growth.
Therefore, for plant lights, it is recommended to use a combination of red and blue LEDs to provide the necessary wavelengths for optimal plant growth. This can be achieved through specialized LED grow lights or by using a mix of red and blue LED bulbs. The specific ratios of red to blue light may vary depending on the plant species and growth stage, but a general guideline is to provide more blue light during the vegetative phase and increase the proportion of red light during flowering and fruiting stages.