Cannabis, like all other green plants, powers its growth thanks to photosynthesis. Photosynthesis takes light energy from the sun, absorbs some of it, and uses that energy to power its processes. These processes include respiration and the development of new plant cells. Molecules called pigments are responsible for absorbing light, and they come in a variety of styles including porphyrins, carotenoids, and anthocyanins. Each of these pigments absorbs and stores different colors of light and uses them for different purposes within the plant. The most active and important of these pigments is the green-appearing chlorophyll, which absorbs blue and red light to power photosynthesis. Carotenoids are orange, red and yellow, and they support chlorophyll. The colors of autumn leaves are because of carotenoids. They absorb blue and green light and help to dissipate free radicals within plants to help them avoid sun damage. Anthocyanins absorb green, yellow, and orange light for cannabis plants. They do this partially to hold it for chlorophyll to pass to them later, but they also seem to store their own energy for other processes that scientists haven’t quite figured out yet. Depending on the pH of whatever they’re in, anthocyanins can appear purple, blue, or red. Anthocyanins are what people see when cannabis turns those lovely deep purple, blue and black colors when exposed to cooler nighttime temperatures near the end of their lives. All of these pigments absorb light and convert it to chemical energy to provide a purpose.
Chlorophyll In Weed Plants
Chlorophyll is a group of pigments in plants that facilitate photosynthesis by absorbing blue and red light. They’re the most important pigments for giving plants the energy they need to survive. The chloroplast, where all the chlorophyll in a plant lives, is the result of a cyanobacteria being consumed without being digested by a plant ancestor cell a billion and a half years ago. Thanks to that, all plants can photosynthesize. Crazy, isn’t it? There are three known types of chlorophyll, called a, b and c. Only a and b are in cannabis plants. Chlorophyll a generally goes around soaking up any strong red and blue light on either side of the spectrum, while chlorophyll b also absorbs the more ambiguous shades like orange and indigo light as well. These pigments absorb light as electromagnetic waves that are turned into chemical energy, called adenosine triphosphate, or ATP for short. This basically charges up chlorophyll molecules and creates a chain reaction among them. This chain eventually reaches the carbon dioxide and water that plants take up through their roots and stomata. They take that buzzy ATP energy and use it to rearrange into a carbohydrate and, typically, an off gas of oxygen. This is the source of both new plant material, in the carbohydrate, and the source of atmospheric oxygen that plants provide. This process is reversed during respiration, which releases ATP and creates water again from the breaking of the same sugar molecules made during photosynthesis. This is how plants build their tissues.
Cannabis Light Dependencies
Cannabis is a high light plant. Its daily light integral, or DLI, is the amount of light a cannabis plant will want in a day overall. It’s measured by taking the light intensity per second the plant likes and adding it up to a cumulative sum over a photoperiod. The ideal DLI for cannabis is somewhere between forty and sixty moles per meter squared of plant surface per day. This is incredibly high for a plant. In fact, research suggests that there is almost no such thing as too much light when it comes to weed, and the more light you give a plant the more it will photosynthesize and create new growth. The problems that occur when a plant gets a lot of light are actually the result of an imbalance in the other components of plant growth in response to the increase in metabolism. Giving a plant more light means needing to give it more water, more nutrients, higher soil oxygenation, and very importantly, more CO2 to give all that extra light energy something to work with. That doesn’t mean just overloading the plant and assuming it will intake things as it sees fit, however. For example, plants that are exposed to a lot of light still need to soak up nutrients at roughly the same quantities they were ingesting them when being grown more slowly, they just do it at a higher rate than before. So a slow and steady leak of nutrients becomes important to maintain.
What Happens To A Cannabis Plant Without Light
Cannabis plants totally deprived of light first engage in a process called etiolation that causes them to stretch up rapidly. Much like when they are young, and the red and far-red light penetrating soil gives young sprouts a direction to grow, cannabis plants deprived of light will believe at first that they are buried. When growing taller fails to produce more light, the chlorophyll in the plant begins to die due to having no photons to turn into ATP, the chemical energy that’s used in the creation of new carbohydrates in the plant. But the plant continues with the process of respiration and starts to release stored ATP energy to help its rapid growth upwards. This is a bit like having the whole process disintegrate from the bottom up, leaving the plant no choice but to wilt, fall over, and die. If a daily light integral, or DLI, is the amount of light a plant likes to have cumulatively over the course of a photoperiod day, the light compensation point, or LCP, is the amount of light that’s needed to keep a plant just barely alive without running into a deficit of ATP and the risk of etiolation. Cannabis plants need around four hundred PPFD for around sixteen hours a day just to survive, which adds up to a DPI of around twenty-three. At that level of light intensity, the plant won’t die but it won’t grow at all either, even though other plants like low light leafy greens will be flourishing.
Light Between Vegetative and Flowering Stages
Original outdoor cultivated cannabis plants have evolved to respond to changes in photoperiod over the seasons. Cannabis sprouts in early spring takes up to three months to grow a full and bushy plant between two and four feet tall, and then produces flowers in deep summer. How does it know when to do these things? As the earth tilts, the sun gets closer to the earth causing a blue shift, and more blue light in the atmosphere in spring. After midsummer, the tilt slowly begins to recede, and more red light appears in the sky as daylight hours wane. Before the advent of sophisticated LEDs, many people swore by using metal halide bulbs for the vegetative phase, switching to high pressure sodium lights during flowering. The reason this switch worked so well is because metal halide bulbs have around thirty percent blue photon emissions, while high pressure sodium bulbs have around four. When plants see blue light, they tend to stay where they are and work on getting bushy rather than getting tall. High pressure sodium bulbs have more red light, making them better for the period when plants are flowering. The intensity of light is measured in a variety of ways using energy, photon flux, and areas as units. Thanks to studies done by NASA working towards growing vegetables in space using LEDs, we know that while full-spectrum light is beneficial for many reasons, it’s particularly the blue and red ends of the spectrum that seem to drive vegetation and flowering.
What Is PAR and PPFD In Marijuana Plants?
PAR stands for photosynthetic active radiation. It’s another way of saying the visible light spectrum though the exact range has been changing, as scientists have been learning more about the role of UV and far-red light in photosynthesis. Generally, it means light between four and seven hundred nanometers in wavelength. PPFD stands for photosynthetic photon flux density, and it’s a measure of the micromoles of photons per meter squared per second. It’s helpful to think of photons as little marbles of light, each with a different color, and they’re falling on a given area in this case a square meter every second. Full sunlight, for example, is considered to be around two thousand PPFD while human office buildings are often lit at around seven PPFD. People used to use PAR to shorten µmols/m2/sec, and the two are used interchangeably in older literature. The only difference is that PAR is sometimes used to denote a measurement of energy output, while PPFD refers to photons over an area and is more scientifically accurate. Scientists think seedlings should only be exposed to a PPFD between one hundred and three hundred. It’s recommended that cannabis plants in the vegetative phase get between three and four PPFD of light. Those in the flowering stage will do well with between eight and twelve hundred PPFD. Anything above that may not be absorbed. Most grow lights give off between one and two thousand photosynthetic photon flux total, which will have fluctuating PPFD readings depending on the distance from the light.
Does Light Contribute To THC Percentage In a Weed Plant?
Light intensity is directly correlated to the health of plants overall, and definitely contributes to the THC percentage in a weed plant. To produce good resin, a plant must have an environment with a low humidity and high air flow. There seems to be some evidence for the idea that UVA and B light in short bursts during flowering can help increase trichome production, thereby possibly increasing THC production. Some growers also swear by giving their plants nothing but blue light during the flushing phase, with reports that it can increase THC and terpene production by up to fifty percent. The percentage of blue photons certainly does play a role in THC production. Recent studies have shown that modern LED lights with a light intensity of at least five hundred PPFD will help to produce more cannabinoids in plants than if they were given only high-pressure sodium lights. Red and far-red light is also implicated in the increased production of THC, thanks to their important role in the development of flowers. This is a very cutting-edge field of study that has only had a few years of testing but has seen enormous results. The legalization of cannabis and subsequent uptick in scientific research on it dovetailed with the explosion in light emitting diode technologies over the last ten years. This has led to fascinating NASA research on using LEDs to grow plants on the space station, which led to the discovery of the roles of the blue, red, and barely-visible far red and ultraviolet spectrums in plant development.
The Best Weed Strain For Growing In Natural Sunlight
Is the technical world of grow lights making your head spin? Weed Seeds has the best strains for growing in plain old sunlight. No sense in collecting a carefully calibrated PPFD optimized and color-balanced crew of LEDs when you can stick a fabric pot in the sun and watch it bloom. The result of a crossing of Big Bud and Skunk, Critical Plus Feminized Seeds can grow up to twelve hundred grams of flowers outdoors! That massive yield can pack up to eighteen percent THC into each gram. The flowers these seeds grow produce a blend of caryophyllene, myrcene, and limonene that creates a spicy, lemon and herbal flavor with notes of pine in the smell of the smoke. The high is creative and uplifting, suitable for quelling anxiety and depression, alleviating stress and pain. This plant takes only eight to ten weeks for its flowers to mature. They’re large, and incredibly resinous. These plants like a temperature between sixty-eight and seventy-eight degrees Fahrenheit while growing, with a relative humidity between forty and fifty percent that gets even lower as it flowers. Keeping the humidity low will ensure that the resin is kept fresh and sticky all the way through, so if they have to be moved into a greenhouse with a dehumidifier that’s alright. When left in a warm and sunny climate with lots of full, intense sunlight, these plants will produce their maximum yields. For these and over six hundred other varieties of premium cannabis seeds, check out Weed Seeds’ selection today!
