Light is one of the most critical factors in cannabis cultivation, because cannabis is a light-loving plant. Now with the legalization of cannabis in some countries and regions, there are more and more indoor cannabis cultivation, so LED plant lights are needed to fill the light, which also opens up the LED plant light market. When using LED plant lights to fill light, different spectral colors play different roles in the growth and development of cannabis plants. Let's learn about it together.
The effect of red light of LED plant lights on cannabis
We know that the red light of LED plant lights can be effectively used for photosynthesis, and the ratio of red to far red of LED plant lights is one of the most critical factors that determine plant morphology, flowering and even sprouting. In the case of cannabis, the R:FR ratio has not been shown to affect flowering time, but its effect on morphology can be demonstrated.
The presence of far-red light and the low R:FR ratio provide a clue to the plant that it is standing in the shadow of another plant, so its energy should be distributed to stem elongation in order to grow taller And get more sunshine.
The effect of blue light of LED plant lights on cannabis
The blue light of LED plant lights has many effects similar to UVA light. Compared with ultraviolet light, blue photons carry less energy, so the response of blue may be milder than ultraviolet light.
The blue light of LED plant lights will increase the concentration of cannabinoids, especially THC. Blue light enhances the compactness of plants and makes plants denser. This is good because very tall, stretched plants cannot support large flower formation. Since there are no blue wavelengths in the spectrum, HPS usually grows tall and thin plants.
The effect of LED plant light green light on cannabis
It has been proven that green can also reduce the activity of secondary metabolites of other species. Adding green to the spectrum will reduce the concentration of anthocyanins in the lettuce. If green light only reverses the biosynthesis of certain secondary metabolites, why should green light be included in the growth spectrum? One is that the green effectively penetrates the leaf layer. The red and blue light is almost completely absorbed by the first leaf layer, and the green effectively passes through the first layer, the second layer and even the third layer. The lower leaf layer can use green light in photosynthesis, so it can also produce yield.
The effect of LED plant light ultraviolet rays on cannabis
UVA light has been shown several years ago to increase the activity of secondary metabolites in many plants, as is the case with cannabis. From the perspective of cannabis growers, the most important secondary metabolites are cannabinoids, such as THC and CBD, and terpenes that give cannabis a unique aroma. Short-wave radiation, such as UVA and blue light, triggers the stress response system of plants, and plants begin to protect themselves from abiotic stress, that is, short-wave radiation. Compared with light sources lacking UVA or blue light, increased pressure levels can lead to increased metabolite activity, which leads to a higher accumulation of THC in flowers.
How much influence does the spectrum of LED plant lights have on plant growth?
The marijuana plant needs bright light, at least some red and blue, for it to grow normally. Although essential for healthy plant growth, it is considered a good form of choosing light of the appropriate spectrum to encourage your desire to grow during the nutrient and flowering period of the cannabis plant.
However, remember that different strains will be affected by different spectra. Some plants are barely affected, while others may respond more strongly. It is important to remember that the changes caused by the spectrum are relatively small (stems tend to grow longer), and many other factors will drive some of the same changes.
On the other hand, if it is to provide a lot of yellow light to the plant, it tends to last very short, because it gets so much light that it has enough blue and does not need to be high. Since almost all led plant growth lights emit a spectrum suitable for healthy cannabis growth, in many ways, the amount of light has a much greater impact on plants than the spectrum.
Tips for supplementing light with LED plant lights for cannabis cultivation:
1. Illumination distance
The illumination distance of the LED plant light is very important. You have to adjust the cannabis at different stages, and the distance should be unified to make the uniformity of the illumination stronger. If the distance is not well controlled, it may harm the growth of cannabis. The general recommendation is that the germination stage distance: 60 cm, the seedling stage distance: 75 cm, the growth stage distance: 45 cm, and the flowering stage distance: 30 cm.
2. Install evenly distributed
Measure the floor area. Multiply the length by the width to get the square meters of the cannabis planting area. You can make the right choice based on how much power to provide per square meter, that is, how many LED plant lights are installed per square meter. In this way, each lamp can be evenly distributed, so that the outer edge will receive strong light, so that the light will be more uniform, and the growth of plants will be more effective.
3. Photoperiod operation
Like many plants, hemp matures with the change of seasons. When the photoperiod is shortened and the light wave is extended, the cannabis plant is prompted to produce flowers or seeds to prepare for the next generation of plants. When growing hemp indoors, growers use LED plant lights to control the photoperiod of plants to achieve better planting results. Although the seedlings grow well under constant light, the vegetative plants should maintain a light cycle of no less than 18 hours. Although some growers expose their vegetative plants to constant light, it is believed that the healthiest and richest plants will experience at least a few hours of darkness in a 24-hour period. Sending a flowering signal to a cannabis plant requires the light cycle to change to 12 hours of light and 12 hours of darkness—no more, no less.
In short, hemp is a kind of light-loving plant, not only has higher requirements on the spectrum, but also has a longer time for supplementing light. Therefore, when purchasing LED plant lights, the spectrum should meet the needs of cannabis supplement light, and the light intensity should be sufficient, but also pay attention to the rest of the plants.
