Photoperiodic cannabis is a timeless classic. Today autoflowering cannabis is on their heels as supposedly being more unpretentious to grow, though of course everything is relative. Nevertheless, photic plants will never be out of demand as a high-yielding and “hardy” variety.

Photoperiodic hemp peculiarities
Perhaps the only thing that can scare off novice growers is the care of photoperiodic plants. At first glance, photoperiodic cannabis may seem to be overly capricious. This manifests itself primarily in the demanding nature of providing certain regimes of day and night during the various stages of the plant’s life. This is why this cannabis is called photoperiodic, because its transition from one stage of development to another depends on the photoperiod, or the length of daylight and dark night. In other words, the photic requires one regime for active growth and strengthening, and a completely different one for flowering and ripening. It is also worth noting that the light regime of autics differs from that of photoperiodic plants, so do not take this article as an instruction manual for all cannabis varieties.

This is because photoperiodic plants have a longer life cycle, and therefore are not suitable for autics in difficult climatic conditions with a short warm (summer, with average daily temperatures not lower than 18-22°C) period of the year. Under indor conditions, the care of lighting plants falls on the shoulders of the grower. And it can be very tiring, because you also have to water and feed the plants, control the temperature, aerate them and exercise them. Isn’t that too much trouble?

But if you look deeper into the subject, you can look at the seeming disadvantages from a different angle – from the advantages.

The advantages of photoperiodic cannabis
Despite some difficulties due to genetics, photoperiodic cannabis varieties have a number of obvious advantages:

Due to their long life cycle, photoperiod hemp is larger and more productive.
By adjusting the light and dark regime, the grower is able to influence the length of the cannabis growing season, plant size, flowering, ripening, and yield.
With the ability to extend the vega, even before flowering begins, you can bring a weakened plant back to normal for whatever reason and thereby save the crop. With autoflowers, such a number does not work.
It’s so convenient to decide for yourself when and how many plants to grow, and when to transfer the cannabis to flowering. All you need to do is to study the requirements and recommendations of experienced growers, to have the necessary lighting equipment, and, just in case, to choose the least capricious varieties for the first grow, like White Widow or Blueberry.

Dependence of light spectrum and photoperiod cannabis response
In order to navigate the desires and needs of photoperiod cannabis, you need to understand the importance of light and dark to it.

Photosynthesis is the main process that sustains the life of any plant in nature. It is a complex chemical process occurring in plant cells containing chlorophyll and carotenoids. These substances absorb light rays of a certain spectrum. This energy is needed to convert hydrocarbons into plant-essential compounds by absorbing carbon dioxide and releasing oxygen.

Light waves of the blue spectrum stimulate the growth of green mass, the formation of branches and leaves, affect th

e growth rate and strengthening of plants from the moment of germination and the entire period of vegetation. A lack of blue spectrum waves leads to weakness of the plant – it seems to stretch upwards instead of bushy, which subsequently reduces the yield.
The red spectrum is important for the formation and strengthening of the root system, as well as flowering and ripening of fruits. It is thanks to the red spectrum, whose rays are especially abundant in natural conditions around late summer and early fall, that the fruits gain weight, bulk up, gain flavor and aroma – in a word, “ripen”.
The green spectrum with its high penetrating power is also important. An excess of such rays “pulls” the plants upward, however, and makes photosynthesis more productive with less leaf pigmentation.
Light Regime
The nature of photoperiodic marijuana is described by several dependencies and requirements:

The plant grows by gaining green mass and enlarging its size during the period of intensive prolonged light, when the length of the light day exceeds 14 hours. Therefore, 18/6 and 20/4 seem to be the optimal day-night regime for the vega period, which is typical for the spring-summer period in the warm climatic zone.
As soon as daylight hours are reduced to 12 hours, i.e. to 12/12 regime, internal mechanisms of natural transition into flowering stage of cannabis are activated. It is precisely at night that the active formation and strengthening of stakes and buds takes place, resin content is accumulated and valuable cannabinoids are accumulated.
There is an important and sometimes crucial point to keep in mind. Photoperiod marijuana requires complete darkness at night and cannot tolerate being disturbed by random flashes of light. While moonlight and starlight are still acceptable in the outdoors, headlights, flashlights, fireworks, and even a nearby campfire can stop the flowering phase and promote hermaphroditism of individuals.