Which grow light to choose for your plants?

Which grow light to choose for your plants?

There are so many options of grow lights in the market that it gets overwhelming trying to find the grow light that is right for your needs. Without getting overly technical, the main things to look at are the colour spectrums of grow lights.


There are mainly purple (blue and red) and full spectrum (white and warm white) grow lights. Although it is believed that blue light promotes plant growth and red light promotes plant budding, recent scientific research and lab tests prove that lights that provide a full spectrum are the ideal choice for your growing space.


Another aspect to consider when choosing the grow lights is that purple colour can be too intense for your eyes. Many people prefer warm white or white colour grow lights that resemble sun light and can be gentle on eyes.


Let's now discuss the technical specifics of grow lights. So what's the difference between blue, red and white lights?


Blue Light Spectrum (400–500 nm)

Blue light spectrum is widely responsible for increasing plant quality – especially in leafy crops. Blue light drives peak chlorophyll pigment absorption which is needed for photosynthesis. 


It’s essential for seedlings and young plants during vegetative stages as they establish a healthy root and stem structure – and especially important when stem stretching must be reduced.  


Red Light Spectrum (600–700 nm)

Red light is known to be the most effective light spectrum to encourage photosynthesis as it’s highly absorbed by chlorophyll pigments. In other words, it sits in the peaks in chlorophyll absorption. Red light wavelengths (particularly around 660nm) encourage stem, leaf, and general vegetative growth – but most commonly, tall, stretching of leaves and flowers. 


A balanced pairing with blue light is necessary to counteract any overstretching, like disfigured stem elongation. It’s important to consider that while red is the most responsive light spectrum for plants, its efficacy really steps in when in combination with other PAR wavelengths.


Warm White (3000k) and Cold White (6000k)


Plants are genetically programmed to grow using sun light, which we consider to be white light, or yellowish-white light. This light looks white because it contains all of the colours of a rainbow, and when these colours are all mixed together they look white.


Many growers actually prefer “warm white” or "white" LEDs. The reason for this, is that at the “warm white” colour temperature, the “ratio” of wavelengths is ideal for plants.


5000K to 6500K is considered full spectrum on the Kelvin colour temperature scale because all light colours are emitted.


Essentially, we know that controlling grow light spectrum can have a significant impact on areas of growth – like flowering, flavour, colour, compactness etc.


However, it’s important to recognise that signalling specific growth factors is part of a much larger, complex cycle. Results also vary depending on the environment (indoor or greenhouse), the relative temperature/humidity, crop species, light intensity (lumens per watt), and photoperiod etc.


Finding the Right Grow Light


There’s a great deal of information and science to take on board as we understand the way plants interact with different light spectrums. Optimising yield production and consistent quality of plants we’ve learned are attributed to light spectrums used together – much like natural sunlight. 


At Grow Plant Shop we sell the grow lights that are full spectrum with combination of red and blue so you can tailor to meet your plant's specific needs. Our LED grow lighting systems are designed and developed using detailed scientific research to give growers the control of using the ideal light spectrum for optimizing the yield, quality, and variability of the plants.


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