When you start researching grow lights, you will quickly learn that there are many different colors of light out there. Why is purple a color for grow lights? Why not blue, green or yellow light?
‘Why are grow lights purple’ is one of the most common questions asked by the growers especially new growers. I guess you have the same wonder, right?
Why do we need this particular spectrum led grow light when we could use any other one?
Technically, no grow lights are purple in nature rather a combination of different colors especially red and blue. You can have a long-day debate on the benefits of purple grow light, even some have doubt on the effectiveness of purple light over plants.
However, Purple light has some amazing benefits and drawbacks – in this article, we are going to talk about the advantages and disadvantages of purple grow lights!
Why are Grow Lights Purple:
Purple grow lights mainly consist of blue and red lights along with IR & UV light.
Red & Blue light:
Blue light is the most important for photosynthesis, while red LEDs are mainly used to produce heat.
IR & UV Light:
IR LED emits an infrared ray which encourages cell division and growth of plants. UV lights have a negative effect on plant development so you should always turn them off during the flowering stage!
The mixed wavelength of red and blue create wavelengths of purple light.
Benefits of Purple Grow Light
Purple grow lights have a wide range of benefits. They are especially beneficial for young, vegetative plants and during the later stages of flowering. Why? Well, let us discuss it in detail!
– It helps promote stem growth and fruit yield while slowing down leaf production. This is because that Purple LED Grow Lights emit a lesser number of wavelengths; hence promoting strong stems with fewer leaves – which means less chance for pests or disease infestation on the plant (and lower time spent by you removing dead leaves). Having more fruits has always been a goal for many indoor gardeners and this is why purple LEDs make sense when growing indoors The article will talk about purple grow light, Why are grow lights purple, advantages and disadvantages of purple grow light.
– Purple LED Grow Light is perfect for cloning as it helps promote rooting in your clones; the increase in root size allows them to absorb more nutrients which will give you healthy plants with a strong establishment period
– It has been found that using purplish tinted LEDs during the early stage of flowering greatly increases overall flower yield
That’s not all! purple grow light has more to offer:
– Purple LEDs produce less heat compared to white diodes which is why they don’t need additional fans or ventilation systems, this saves your electricity bill!
– The purple spectrum stimulates chlorophyll production and photosynthesis process without emitting too much heat. This encourages better yield even if plants are grown in an enclosed space with limited natural sunlight.
But do not forget: Not all plants require purple color wavelength so be sure to check out plant requirements before deciding on a LED light type for growing purposes. Growers often use pink grow lights during the vegging stage but we would recommend blue/white LEDs for the flowering stage.
Best Purple LED Grow Lights:
Top purple LED grow lights on the market include King LED, VIPARSPECTRA, and PHLIZON.
How do I choose a good Purple grow lights:
There are some factors that should be taken into consideration when choosing the best purple led grow light for growing cannabis including price, quality & warranty period offered by the manufacturer, color spectrum emitted (you want a balanced combination of red and blue diodes), the intensity of the light, weight, and dimensions.
You can check our pickings for 2X2 & 4X4 grow tents or space. Also, our listing of cheap LED grow light covers some best purple grow lights on the market.
Drawbacks of Purple Grow Light:
Purple grow light to have some drawbacks also! Why are purple lights not recommended for growing plants?
– It is difficult to determine the correct amount of blue and red color needed in a single LED or even in an entire system. Consequently, this can lead to a nutrient deficiency which slows down the growth cycle in your garden space.
It’s all about balance – when you use too many blue LEDs, it will slow down the plant’s growth while using more red diodes increases internode length without providing any extra yield return on investment (ROI). This makes finding the right combination very challenging for growers who are new to the deep learning process of hydroponics gardening.
– Fail to provide sufficient warmth for plants during the vegetative stage.
A common notion about LED grow light:
This is a very common misconception among new growers that LEDs don’t emit heat, while this isn’t completely true, it’s not entirely false either! You cannot compare them directly with HPS or MH bulbs because different lighting technologies have their own pros and cons.
In fact, blue light has been proven to reduce the amount of thermogenesis in your plant compared to the red color spectrum. Without proper warming, you can easily get yourself into trouble when growing cannabis indoors without any ventilation system!
Health concerns due to purple light:
There are some health concerns of purple grow light as well.
-Some studies have shown that this color has been linked to cell death in plants.
-It can affect your health too. Too much exposure to purple grow light can make you feel drowsy. Even further, It can reduce your sexual desires!
So Why would you use purple lights when growing cannabis? Why aren’t they recommended for every stage of the growth cycle? The answer is simple! Purple LEDs don’t emit enough heat, which makes them a great choice for the seedling and cloning phase but not suitable during the flowering or fruiting stages.
This is why we recommend using white or blue LED Grow Lights instead – it’s all up to your personal preference so be sure to test everything before making a final decision on what type of lighting system will work best for your indoor plants.
To know the effects of grow light on pets particularly cats, you can check our other article.
Final Thoughts on Purple Grow Light:
Purple grow lights have both advantages and disadvantages but you need to find the right balance between them! Why are purple LED Grow Lights not recommended for every light cycle? It is mostly due to a lack of sufficient heat emission.
However, using these can be advantageous if your plants are seeded or cloned. For the flowering stage, we recommend using more blue/white LEDs instead since it will provide better canopy penetration with a limited risk of burning leaves during this important growth phase.