The Importance of Infrared (Far-Red) Light for Marijuana Growing

Approximately 10,000 years ago, humans started domesticating plants and animals. By doing so, they could escape the nomadic lifestyle and transition to building long-lasting communities. Agriculture has come a long way since then, and the development of technological tools and knowledge will further change the landscape.
Before, all we knew to offer plants were sunlight, water, and soil for nutrients. Today, farms are looking at temperature and moisture sensors, infrared light for plants, robots, and even GPS technology to grow their yields. With indoor gardens, we are no longer limited to depending on the natural climate. Technology will allow agricultural operations to grow profitably, efficiently, and safely, all the while remaining environmentally friendly.
Color Spectrums and Cannabis Cultivation
By now, you should be fully aware that growing marijuana involves more than just the regular old acts of watering and harvesting. The truth is, light plays a significant role in how fast or slow your plant grows and how big or small it ends up.
Let’s take a deep dive into the color spectrum, specifically in regards to far-red (FR), to understand how different wavelengths affect growth. Some colors promote stem development and help you achieve bigger and healthier leaves, while others boost THC production. By understanding how to implement the best lighting conditions for your plants, you’ll create an environment for them to thrive
What Is Far-Red Light?
Far-red light lies at the furthest red end of the spectrum, just before infrared. The wavelength is between 700 and 750 nm, making it just dimly viewable by humans. Plants largely reflect and transmit far-red light, and it plays a vital part in plant yield.
What Infrared (Far-Red) Lights Can Do for Cannabis Plants
A growing number of horticulturalists are advocating the use of far-red lights for cannabis plants. While FR does not directly drive photosynthesis, it does support the process in other ways. Red wavelengths trigger a biological reaction in plants, telling them to activate growth mode. Used correctly, the light will bring out your cannabis’ full potential. Let’s look at the many benefits of FR.
Supports Photosynthesis
Plant leaves only absorb about 30% of FR and largely reflect and transmit it. However, experts consider the light to affect the photosynthesis process minimally. It’s important to note that the positive effects increase when the far-red photons interact with those of shorter wavelengths. Recent studies also show additional efficiency in photosynthesis when cannabis plants receive simultaneous exposure to shorter and longer wavelengths.
Offers Higher Cannabinoid Content
The major cannabinoids are CBGA, CBDA, THCA, and CBCA. Thanks to studies conducted, we now have proof of the hypothesis that the light spectrum plays a significant role in plant development and cannabinoid content and profile.
Increases Light Capturing
Far-red LED growth lights serve many purposes for plants. Aside from being a source of energy for photosynthesis, it also provides information to plants about their environment. When cannabis plants sense an increase in FR photons, they consider themselves shaded and at risk of competition. Because of this, they will try to outgrow the other plants by increasing their height and leaf sizes. Bigger leaves will provide additional light capture, which will directly impact yields.
Regulates Flowering
Plants reproduce according to the seasons, except those sitting on the equator. Most also regulate their flowering period based on the dark hours. Cannabis is a short-day plant, which means that they flower on long nights. By using a far-red light system, you stand to shorten the time flowers require to initiate and set by up to 15%.
Enhances Flower Size
Growers that cultivate their cannabis plants with far-red lights during the flowering period will find that their buds are bigger and much more potent. If you intend to maximize your crop, this is one benefit you’ll want to note. Powerful buds undoubtedly fetch higher prices in the market, and thus configuring your growing environment to include the far-red waveband is a profitable move indeed.
Maximizes Harvest
Even if you’re a novice, you’ll know that light significantly affects marijuana yield. However, a good harvest is more than just constantly exposing your plants to bright light. Cannabis plants benefit from regulated cycles of different wavelengths, and your settings will also depend on the different phases.
Shortened Crop Cycle
By correctly applying FR light, you’ll see a sped-up crop cycle. Make sure to implement suitable configurations depending on the growth stage and daily light cycle. Too much far-red light during the vegetative stage will result in lanky plants that struggle to hold up their flowers. The best times to turn on your FR lights would be 10 minutes before and after the photoperiod.
Builds Resistance
Far-red light helps build a crop’s tolerance against low temperatures and salt. This means that your cannabis plants will be able to withstand harsh weather and soil conditions. You’ll see this come into good use should you move your herbs from one place to another, as they are highly susceptible to shock.
Maximize Every Cannabis Growth Stage With LED Grow Lights
Merely turning on your infrared grow lights at the default setting will help your cannabis thrive, but that’s not taking full advantage of this tool. From seed to harvest, you can maximize each growth stage with different spectrums. You’ll want to skip the convenience and fine-tune your grow lights to not just quicken the phases but bring upon a great harvest as well. Let’s look at some crucial considerations.
The Seedling Stage: Fresh Beginnings
Your cannabis plants need light to grow from the moment they start sprouting. However, it’s important to note that at this stage, they’re more sensitive to intense light compared to later phases. You’ll want to control your LED lights so that they’re not too strong. A dim intensity is best for now.
If your setup doesn’t allow dimming, don’t fret. You can take a slightly different approach by moving your lights further away. If you do this, ensure not to place them too far away, because that will result in spindly and lanky plants.
Alternatively, look for a setting on your LED lights that will give you a cooler bluish tint. This might also be under a configuration called “vegging.” This will produce a spectrum that’s optimal for your seedlings. As for timing, aim for around 18 hours with your lights on and 6 hours off.
The Vegetation Stage: Grow, Baby, Grow!
When your plants grow taller and stronger, they enter the vegetation stage. This is a robust growing stage, which means that you can gradually increase the intensity of your marijuana grow light.
During vegetation, you can stay with the same time settings as the seedling stage, which is 18 hours on and 6 hours off. You’ll also want to test having the lights on for longer to maximize the vegetative growth. Make sure to monitor what’s happening while performing your tests to grow the best cannabis plants.
You aim to grow plants that are healthy and bushy. You’ll know if your cannabis isn’t getting enough light; if it starts looking thin and underfed, it’s time to push the intensity. You can do this by putting your LED grow lights closer or adjusting the dimmer.
The Flowering Stage: Time to Induce the Bloom!
You can stay at the vegetation stage until you’re satisfied with your plants’ sizes. When you feel that they’re big enough, you can move on to the flowering stage. Keep in mind that this new phase might result in a massive amount of stretching, especially during the early part. Knowing when to switch stages is vital.
If you’re planting cannabis outdoors, the plants start flowering in late summer. This is when daytime gradually gets shorter. To simulate nature, you can induce the blooming period by adjusting the time your lights are on versus off. Set your LEDs to turn on and off for an even 12 hours each, uninterrupted. Additionally, look for a flowering switch on your setup and turn it on.
For the best results, ensure that your grow room doesn’t have an external light source. You do not want some sunlight coming in to confuse the plants and bring back the vegetative state or cause hermaphroditism.
At this time, you’ll want to maximize the intensity of your LED grow lights or move them closer to your plants. But remember, any change must be done gradually. You do not want to shock your plants with sudden environmental switches, be it with light or temperature.
Let’s Look at the Big Picture
Along with the benefits of the IR LED grow light come some unsavory effects. Firstly, you’ll find that FR represses seed germination. This happens due to the inactivation of phytochrome photoreceptors. Root growth will also see some inhibition, especially with mismanaged exposure.
All of this is to say that far-red light is beneficial, but not without the right knowledge and configuration. Marijuana growers must determine the optimal dose of FR light for their crops. With longtime studies come rich data, and that’s one sure way to derive the best environment for thriving cannabis plants.