Spectrum Break Down
| Sean Phillips
Light is the most important part to a plant’s growth. Plants use visible spectrums of light in the process of photosynthesis. Some wavelengths are more important than others depending on what you are trying to do in your garden. The right duration, intensity and spectrum will help aide you in horticulture.
Blue light is a radiation with wavelengths between 450 to 495nm. The most important being from 430 – 450nm. This wavelength is a visible wavelength. Blue light has a relatively high energy concentration and has pronounced effects on plant vegetation as well as flowering believe it or not. Plants grown with blue light in a vegetative state generally have thick dark leaves in comparison to those that are not. Tighter internodal spacing may also be examined. When flowering using some blue light, growers will experience less stretching. Higher terpene levels can also be achieved. Blue light also regulates the opening of the stomata which is located on the bottom of the leaves. The stomata controls the amount of carbon dioxide a plant can absorb and how much transpiration will occur aka water loss.
Red light is also a radiation with wavelengths between 620 – 700nm. The most important being from 640 – 680nm. This wavelength is also visible. Red light encourages stem growth, vegetative, flowering and chlorophyll production. Red light also helps the peak of chlorophylls utilizing photosynthesis to help produce sugar and carbon. Sugars and carbons are essential in a plant growth cycle. Basically, the building blocks for plants on a cellular level. Growing with red light alone can exhibit plant symptoms such as long internodal spacing. Skinny stems would also be examined, which prohibit xylem and phloem flow.
Green light, a radiation as well with wavelengths between 495 – 570nm. Also, a visible wavelength. Green light is the mysterious wavelength. Not a whole lot is known about this wavelength because, most green light is reflected off the plant’s leaves. Therefore, it has a much smaller role in plant growth. There are some important parts of these photons that are beneficial. Green light is a tool for stomatal control, phototropism and photomorphogenic growth. Another potential advantage of green light is that it can penetrate a canopy better than other wavebands of light.
Compared to red light alone, the red-blue light combination also increases plant size, leaf number, leaf size, and chlorophyll content. Combining all three forms of light, green light completes a comprehensive spectral treatment in understanding a plants activity. Our growth on knowledge about how plants respond to light will identify key light combinations ultimately helping growers improve the yield and quality of their crop.